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Developing Free-range Animal Production Systems A report for the Rural Industries Research and Development Corporation By Phil Glatz and Yingjun Ru December 2004 RIRDC Publication No 04/058 RIRDC Project No SAR-30A

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© 2004 Rural Industries Research and Development Corporation. All rights reserved. ISBN 0 642 58768 X ISSN 1440-6845 ‘Developing Free-range Animal Production Systems’ Publication No. 04/058 Project No. SAR-30A The information contained in this publication is intended for general use to assist public knowledge and discussion and to help improve the development of sustainable industries. The information should not be relied upon for the purpose of a particular matter. Specialist and/or appropriate legal advice should be obtained before any action or decision is taken on the basis of any material in this document. The Commonwealth of Australia, Rural Industries Research and Development Corporation, the authors or contributors do not assume liability of any kind whatsoever resulting from any person's use or reliance upon the content of this document. This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186. Researcher Contact Details Dr Phil Glatz South Australian Research and Development Institute PPPI, Roseworthy Campus Roseworthy, SA 5371. Phone: (08) 83037786 Fax: (08) 83037689 e-mail: [email protected] Dr Yingjun Ru South Australian Research and Development Institute PPPI, Roseworthy Campus Roseworthy, SA 5371. Phone: (08) 83037787 Fax: (08) 83037797 e-mail: [email protected] In submitting this report, the researcher has agreed to RIRDC publishing this material in its edited form. RIRDC Contact Details Rural Industries Research and Development Corporation Level 1, AMA House 42 Macquarie Street BARTON ACT 2600 PO Box 4776 KINGSTON ACT 2604 Phone: 02 6272 4819 Fax: 02 6272 5877 E-mail: [email protected] Internet: http://www.rirdc.gov.au Published in December 2004 Printed on environmentally friendly paper by Canprint

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Foreword In Australia, climatic extremes and environmental pollution concerns have limited the use of pigs and poultry in free-range systems. Nevertheless there is a growing consumer demand for greener and chemical free pork and free-range eggs. Pigs and poultry, housed in eco shelters, were integrated into a pasture crop rotation system to establish if free-range pig and poultry operations associated with organic grain production could be used on a niche scale in the wheat belt of Australia. Pigs and poultry were successfully integrated into the rotation and could be used in the same way sheep are used in the wheat belt with benefits to soil fertility and potential for weed control. Performance of batches of pigs was comparable to intensive standards and the production of egg layers in the free-range system generally matched the industry benchmark. A concern however was the predation of poultry by foxes. This project was funded from industry revenue, which is matched by funds provided by the Federal Government and is an addition to RIRDC’s diverse range of over 1000 research publications. It forms part of our Resilient Agricultural Systems, which aims to foster agri-industry systems that have diversity, flexibility, and robustness to be resilient Australian Agriculture. Most of our publications are available for viewing, downloading or purchasing online through our website: downloads at www.rirdc.gov.au/fullreports/index.htm

purchases at www.rirdc.gov.au/eshop

Dr Simon Hearn Managing Director Rural Industries Research and Development Corporation

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Acknowledgments The authors are grateful for the following support;

• Funding from the Resilient Farming Systems Sub Program of the Rural Industry Research and Development Corporation.

• Mr Hugh Reimers from the Department of Agronomy and Farming Systems, University of Adelaide who provided advice on pastures, crops and fencing.

• Mrs Belinda Rodda, Mrs Sandy Wyatt, Mr Michael Fischer, Mr Geoff Wyatt, and Ms Kylee Swanson from the Pig and Poultry Production Institute who conducted the field trials and chemical analysis of pasture samples.

• Dr Zhihong Miao who undertook the literature reviews. • Mr Peter Cornelius and Mr Chris Hill from the Department of Agronomy and Farming

Systems, University of Adelaide who planted the crops and pastures and installed the fencing.

• Mrs Maggie Beer, from the SA Primary Industry Research and Development Board who provided advice on free-range farming and products.

• Mr Peter Jones, who installed the eco housing for the free-range pig and poultry trial. • Mrs Meg Parkinson, from the Free-range Egg Producers Association of Australia, for her

specialist advice on free-range poultry farming. • Mrs Christine Ross for her specialist input on free-range pig farming.

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Contents

FOREWORD...................................................................................................................................... III ACKNOWLEDGMENTS.................................................................................................................. IV LIST OF TABLES ............................................................................................................................. VI EXECUTIVE SUMMARY................................................................................................................ IX INTRODUCTION.................................................................................................................................1 LITERATURE REVIEW.....................................................................................................................4

Free-range poultry production-a review.............................................................................................. 4 Review of Production, Husbandry and Sustainability of Free-Range Pig Production Systems........ 24

METHODOLOGY..............................................................................................................................44 Management Committee ................................................................................................................... 44 Measurements.................................................................................................................................... 45

RESULTS.............................................................................................................................................47 Committee Involvement .................................................................................................................... 47 Phase 1. Comparison of forage, soil and botanical parameters in a medic pasture before and after grazing by poultry and sheep, and pigs and sheep ............................................................................ 47 Phase 2. Comparison of forage, soil and botanical parameters in a wheat stubble before and after grazing by poultry and sheep and pigs and sheep ............................................................................. 59 Phase 2. Comparison of forage, soil and botanical parameters in a wheat stubble before and after grazing by poultry and sheep and pigs and sheep ............................................................................. 59 Phase 3. Comparison of forage, soil and botanical composition in a regenerated medic pasture paddock before and after grazing by poultry and sheep and pigs and sheep..................................... 86

DISCUSSION ....................................................................................................................................118 Phase 1 (year 1)- Integration of poultry into a medic pasture during the late growing season of the pasture. ............................................................................................................................................ 118 Phase 2 (year 2)- Integration of poultry into wheat stubble. ........................................................... 119 Phase 3- Integration of poultry into a regenerated medic pasture. .................................................. 120

REFERENCES ..................................................................................................................................123 PUBLICATIONS ..............................................................................................................................135

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List of Tables Table 1. Comparison of the agronomic, snail, weed and soil fertility in paddocks grazed by sheep and poultry

(Glatz and Ru, 2002) ......................................................................................................................................8 Table 2. Effect of season on crop contents of scavenging local hens (physical observation) (Tadelle and Ogle,

2000) ..............................................................................................................................................................9 Table 3. Effect of altitude on crop contents of scavenging local hens (physical observation) (Tadelle and Ogle,

2000) ............................................................................................................................................................10 Table 4. Chemical composition of the crop contents of scavenging hens, overall means, SD and range from three

of the seasons and study sites (Tadelle and Ogle, 2000) ..............................................................................10 Table 5. Chick starter and pre-lay feed specifications (Portsmouth, 2000)...........................................................12 Table 6. Sample size, prevalence of gastrointestinal helminth infections in Danish poultry (Permin et al., 1999)13 Table 7. Drug sensitivity tests on 1248 E coli strains isolated from university battery poultry, 2196 strains from

commercial battery poultry, 1220 strains from free-range town poultry and 1064 strains from village poultry in tropics (Ojeniyi, 1985).................................................................................................................14

Table 8. Production performance of free-range birds compared to strain specifications over 18-40 weeks (Glatz and Ru, 2002) ...............................................................................................................................................15

Table 9. Edible energy outputs and efficiencies of usage of fossil fuel energy (Wathes, 1981)...........................16 Table 10. Mean values of nutrient (per kg egg, edible weight†) in eggs under different systems of management

(Tolan et al., 1974) .......................................................................................................................................17 Table 11. Fatty acid composition (g/kg total fatty acids) of the yolk fat from hens mixed feed in cages (MF) or

mixed feeds and grass under free-range conditions (FR) (n=22) (Lopez-Bote et al., 1998) ........................18 Table 12. quarterly mean values (per kg egg, edible weight) for nutrients which showed a significant seasonal

pattern in uk (tolan et al., 1974) ...................................................................................................................18 Table 13. Pesticide residues (ppm) in eggs from agricultural institute farms without thermal vaporisers (Holmes

et al., 1969)...................................................................................................................................................19 Table 14. Effects of foraging material and food form on the percentages of hens engaged in different activities

in scan samples. Means as well as minimum and maximum values (in parentheses) of 4 pens per housing condition, P values derived from ANOVA (Aerni, et. al., 2000) .................................................................20

Table 15. Ambient temperature in relation to evaporative critical temperature (ECT) for the sow and its effect on the predicted1 performance of a sow and litter during a 28-day lactation (post-partum body weight of 150 kg, fed a diet containing 13.5 MJ DE and 164 g crude protein per kg dry matter, litter size of 9, no creep feed provided) (Black et al. 1993)................................................................................................................28

Table 16. Effectiveness of a wallow and water spray on the growth of swine (Culver et al., 1960)....................29 Table 17. Least squares means and standard errors for production performance of Newsham sows and piglets

housed indoors vs outdoors over two parities from January to September 1999 (Johnson et al., 2001) ......31 Table 18. Least square means and standard errors for sow and piglet performance by season (Stansbury et al.,

1987) ............................................................................................................................................................32 Table 19. Least square means and standard errors for sow and piglet performance in different farrowing house

temperatures (Stansbury et al., 1987) ...........................................................................................................32 Table 20. The effect of housing within season on production performance adjusted to an off-farm (finishing)

weight of 105 kg (Sather et al. 1997) ...........................................................................................................33 Table 21. Least squares means and standard errors for behaviour performed by Parity-2 Newsham piglets

indoors vs outdoors from January to March 1999 (Johnson et al., 2001).....................................................35 Table 22. Least squares means and standard errors for behaviours performed by Parity-2 Newsham sows indoor

vs outdoor from January to March 1999 (Johnsen et al., 2001)....................................................................36 Table 23. Frequency of behaviour in relation to feed level corresponding to 80 or 100% of indoor

recommendations (Stern and Andresen, 2003).............................................................................................36 Table 24. Proportion of recordings of behavioural elements in relation to stocking rate (Andresen and Redbo,

1999) ............................................................................................................................................................37 Table 25. Helminths found in pigs in relation to type of management (Nansen and Roepstorff, 1999) ..............38 Table 26. Herbage availability in the medic paddocks grazed by poultry and sheep...........................................48 Table 27. Botanical composition and snail number in the medic paddock grazed by poultry and sheep ............48 Table 28. Chemical composition (%) of herbage in medic paddocks ..................................................................49 Table 29. Number of weeds in the herbage grazed by sheep and poultry in the medic pasture paddocks............50 Table 30. Soil nitrogen and pH in the medic pasture before and after grazing ....................................................51 Table 31. Production performance of free-range birds compared to strain specifications over 18-40 weeks......51 Table 32. response of respondents in taste test comparing cage and free-range eggs for flavour, colour and

texture...........................................................................................................................................................64

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Table 33. Herbage availability (g/m2) in the paddocks during the grazing season..............................................53 Table 34. Snail number changes before, during and after grazing .......................................................................53 Table 35. Botanical composition of herbage grazed by sheep and pigs...............................................................54 Table 36. Chemical composition (% air dry basis) of herbage grazed by sheep and pigs during the season.......55 Table 37. The number of weeds in the paddocks grazed by sheep and pigs during the season ..........................56 Table 38. Soil fertility in paddocks grazed by pigs and sheep during the season ................................................57 Table 39. The performance of grazing pigs on barley and medic pasture paddocks in summer..........................57 Table 40. Response of respondents in taste test comparing free-range pork (flavour, colour, texture and

juiciness) and intensively produced pork. ....................................................................................................58 Table 41. Herbage characteristics; soil nitrate, pH and penetrometer readings for hens before and after grazing

on wheat stubble...........................................................................................................................................59 Table 42. Herbage characteristics; soil nitrate, pH and penetrometer readings for sheep before and after grazing

on wheat stubble...........................................................................................................................................59 Table 43. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after

grazing by hens.............................................................................................................................................61 Table 44. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after

grazing by sheep...........................................................................................................................................61 Table 45. Dry matter, ash; soil nitrate, ammonia and pH readings for hens and sheep before and after grazing on

wheat stubble................................................................................................................................................62 Table 46. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and

sheep paddocks before and after grazing on a regenerated medic pasture. ..................................................62 Table 47. Weight of weeds in poultry and sheep paddocks after grazing on a wheat stubble ..............................63 Table 48. Nitrate, Ammonia and pH for poultry and sheep in different zones before and after grazing on wheat

stubble ..........................................................................................................................................................64 Table 49. DM and Ash for poultry and sheep in different zones before and after grazing on wheat stubble ......64 Table 50. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in wheat

stubble before and after grazing by hens ......................................................................................................65 Table 51. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in wheat

stubble before and after grazing by sheep ....................................................................................................66 Table 52. Weight of weeds in different zones after grazing by poultry and sheep on wheat stubble paddock ....68 Table 53. Penetrometer readings in poultry and sheep paddocks before and after grazing on a wheat stubble...69 Table 54. Wheat quality and yield in poultry and pig paddocks ..........................................................................72 Table 55. Wheat quality in zone 1 and 2 of sheep and chicken paddock .............................................................72 Table 56. Herbage characteristics; soil nitrate, pH and penetrometer readings for pigs before and after grazing on

wheat stubble................................................................................................................................................73 Table 57. Herbage characteristics, soil nitrate, pH and penetrometer readings for sheep before and after grazing

on wheat stubble in the pig free-range system .............................................................................................73 Table 58. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after

grazing by pigs on wheat stubble .................................................................................................................74 Table 59. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after

grazing by pigs on wheat stubble .................................................................................................................74 Table 60. Dry matter, ash; soil nitrate, ammonia and pH readings for pigs and sheep before and after grazing on

wheat stubble................................................................................................................................................75 Table 61. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and

sheep paddocks before and after grazing on a regenerated medic paddock (No./0.1m2) (n=4)...................76 Table 62. Numbers of seeds, weed seeds and weeds in poultry and sheep paddocks after grazing on a regenerated

medic paddock..............................................................................................................................................78 Table 63. Nitrate, Ammonia and pH in wheat stubble paddocks grazed by pigs and sheep in different zones

before and after grazing................................................................................................................................80 Table 64. Herbage availability, medic, wheat seed numbers and snail numbers for different zones in wheat

stubble before and after grazing by pigs and sheep......................................................................................82 Table 65. Numbers of seeds, weed seeds and weeds in different zones after grazing by pigs and sheep on wheat

stubble paddock............................................................................................................................................84 Table 66. The performance of pigs grazing on wheat stubble ..............................................................................85 Table 67. Yield, crude protein (CP) and digestible energy (DE) of grain harvested from pig-sheep trial ...........85 Table 68. Zone comparison for CP and DE of wheat harvested in the pig and sheep paddocks...........................85 Table 69. Herbage characteristics; soil nitrate, pH, penetrometer readings and insect numbers for hens before and

after grazing on regenerated medic pasture..................................................................................................86 Table 70. Herbage characteristics; soil nitrate, pH, penetrometer readings and insect numbers for sheep before

and after grazing on regenerated medic pasture. ..........................................................................................86

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Table 71. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by hens.............................................................................................................................................87

Table 72. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by sheep...........................................................................................................................................88

Table 73. Numbers of weeds before and after grazing by poultry on a regenerated medic pasture......................90 Table 74. Numbers of weeds before and after grazing by sheep on a regenerated medic pasture ........................90 Table 75. Dry matter, ash; soil nitrate, ammonia and pH readings for hens and sheep before and after grazing on

wheat stubble................................................................................................................................................91 Table 76. Penetrometer reading before and after grazing by poultry, pigs and sheep on a regenerated medic

pasture ..........................................................................................................................................................91 Table 77. Insect numbers (No./0.1m2 ) before after grazing by poultry and sheep on regenerated medic pasture

......................................................................................................................................................................92 Table 78. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and

sheep paddocks before and after grazing on a regenerated medic pasture. ..................................................93 Table 79. Numbers of weeds in poultry and sheep paddocks after grazing on a regenerated medic paddock. .....95 Table 80. Dry matter, ash, nitrate, ammonia and pH for poultry and sheep in different zones before and after

grazing on regenerated medic pasture. .........................................................................................................97 Table 81. Insect numbers (No./0.1m2 ) before after grazing by poultry and sheep in the different zones on the

regenerated medic pasture ............................................................................................................................98 Table 82. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in a

regenerated medic pasture before and after grazing by hens.......................................................................99 Table 83. Numbers of weeds in different zones after grazing by poultry and sheep on wheat stubble paddock 101 Table 84. Penetrometer reading before and after grazing by poultry and sheep on a regenerated medic pasture102 Table 85. herbage characteristics, soil nitrate, pH and Penetrometer readings for pigs before and after grazing on

regenerated medic pasture ..........................................................................................................................116 Table 86. herbage characteristics, soil nitrate, pH and Penetrometer readings for sheep before and after grazing

on regenerated medic pasture .....................................................................................................................116 Table 87. Herbage availability, medic and wheat seed numbers and snail numbers for regenerated medic paddock

before and after grazing by pigs .................................................................................................................104 Table 88. Herbage availability, medic and wheat seed numbers and snail numbers for regenerated medic paddock

before and after grazing by sheep...............................................................................................................104 Table 89. Numbers of weeds before and after grazing by pigs on a regenerated medic pasture........................106 Table 90. Numbers of seeds, weed seeds and weeds before and after grazing by sheep on a regenerated medic

pasture in the pig free-range system...........................................................................................................106 Table 91. Dry matter, ash; soil nitrate, ammonia and pH readings for pigs and sheep before and after grazing on

wheat stubble..............................................................................................................................................107 Table 92. Insect numbers (No./0.1m2 ) before after grazing by pigs and sheep on the regenerated medic pasture

....................................................................................................................................................................107 Table 93. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for pigs and

sheep paddocks before and after grazing on a regenerated medic paddock. ..............................................108 Table 94. Numbers of weeds in poultry and sheep paddocks after grazing on a regenerated medic paddock. ...110 Table 95. Nitrate, ammonia and pH in regenerated wheat stubble paddocks grazed by pigs and sheep in different

zones before and after grazing....................................................................................................................112 Table 96. Insect numbers (No./0.1m2 ) in the zones and control area of paddocks grazed by pigs and sheep on

the regenerated medic pasture ....................................................................................................................113 Table 97. Penetrometer readings in the zones and control area of paddocks grazed by pigs and sheep on the

regenerated medic pasture ..........................................................................................................................113 Table 98. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in

regenerated medic pasture before and after grazing by pigs and sheep......................................................114 Table 99. Numbers of seeds, weed seeds and weeds in different zones after grazing by poultry and sheep on

regenerated medic pasture. .........................................................................................................................116 Table 100. Daily gain, carcass weight, backfat and dressing percentage of pigs foraging on regenerated medic

pasture ........................................................................................................................................................117

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Executive Summary Pigs and poultry, housed in eco shelters, were integrated into a pasture crop rotation system to establish if free-range pig and poultry operations associated with organic grain production could be used on a niche scale in the wheat belt of Australia. Comparison was made with sheep, which are traditionally used in this system. Free range pigs In the first year of the project free-range pigs, were allowed to forage medic pastures in a crop-pasture rotation. Half the pigs also had access to barley stubble. Two batches of pigs were grown in the first year. While the summer temperatures during this period were the highest in a century no pig performed abnormally. Pigs did not suffer from sunburn being protected by a coat of mud on the skin from the wallow. Performance of the first batch of pigs was comparable with intensive industry standards with daily weight gain 600-800 g, back fat 14-17 mm and dressing percentage over 74%. The pigs grazing the barley crop paddocks were heavier and fatter. Daily gain (500-700 g) of second batch of pigs was less than the first batch because availability of stubble and forage decreased. In the second year of the project a wheat crop was grown in paddocks, in which sheep and free-range pigs had previously foraged on medic and barley pastures. Yield of wheat from pig paddocks was 2.94 tonnes/ha and 3.06 tonnes/ha from sheep paddocks. After the wheat harvest, a new batch of pigs and poultry were allowed to forage on the mulched wheat stubble. After grazing, the soil nitrate and penetrometer readings increased in both the sheep and pig paddocks. Both pigs and sheep foraged quite widely in the wheat stubble paddocks, which resulted in an overall increase in soil nitrate levels. By the end of the grazing period the penetrometer readings in both sheep and pig paddocks increased from trampling of the soil and drying out of the paddocks. Sheep grazed more of the medic pods than pigs. One batch of pigs was grown out over the period January-May. Performance was once again comparable with industry standards with daily weight gain of groups ranging from 573-763 g, back fat 7.5-11 mm and dressing percentage 76%. In the third year of the project pigs were allowed to forage on a regenerated medic pasture. The daily gain of pigs grazing on the regenerated medic pasture averaged 450 g/day for male pigs and 518 g/day for female pigs. This result was lower than daily gain achieved in the previous growth trials. The major difference was that the trial was conducted in winter with pigs exposed to the cold conditions and pigs were younger when they were introduced into the system. Pigs reduced growth to compensate for the cold conditions. Pigs showed a propensity for grazing rye grass, barley grass and other broad leaf weeds while sheep foraged sheep preferred broad leaf weeds in the regenerated medic pasture. Soil fertility and pH in sheep and pig paddocks were not different, suggesting that pigs could be used in grazing systems without detriment to the soil. However care needs to be exercised and pigs only used where sufficient forage is available. Traditional free-range pig systems generally result in a landscape denuded of forage, which has serious environmental consequences. After grazing, the number of weeds in the paddocks was similar between the species indicating an ability of both pigs and sheep to control weeds equally as well. Pigs spent most of their time under the trees and a similar amount of time in the shelter and in the zone closest to the shelter.

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Free-range poultry In the first year of the project free-range poultry, were allowed to forage medic pastures in a crop-pasture rotation. The production performance of egg layers (Hyline Brown) in the free-range system was compared with the production specifications published by the Hyline Company for the strain housed under cage systems. The free-range birds showed higher levels of mortality and lower rates of lay, egg weight and body weight over the period 18-40 weeks. The reduction in performance of birds relative to the benchmark was expected considering the heat wave conditions experienced. Despite this the pasture phase of the free-range system was considered successful. Sheep, however, were very effective in grazing the wire weed, which contaminated the paddocks whereas poultry avoided this weed. In contrast, the number of unidentified weeds in the sheep paddock was greater than the poultry paddock. This raises the possibility that sheep and poultry could be grazed together in some circumstances, to provide a method for reducing weed build up, using sheep to graze out weeds they prefer and poultry to consume weed seeds that sheep avoid. Soil fertility was not different between the sheep and poultry paddocks. After the wheat harvest, a new flock of hens were allowed to forage on the mulched wheat stubble. In the second year of the project wheat crop was grown in paddocks, in which sheep and free-range pigs and poultry had previously foraged on medic and barley pastures. In the poultry trial yield of wheat from poultry paddocks was 1.25 tonnes/ha versus 1.43 tonnes/ha from sheep paddocks. For the pig trial yield of wheat from pig paddocks was 2.94 tonnes/ha and 3.06 tonnes/ha from sheep paddocks. After the wheat harvest, a new batch of pigs and poultry were allowed to forage on the mulched wheat stubble. After grazing the soil nitrate and penetrometer readings increased in both the sheep and pig paddocks. Both pigs and sheep foraged quite widely in the wheat stubble paddocks, which resulted in an overall increase in soil nitrate levels. By the end of the grazing period the penetrometer readings in both sheep and pig paddocks increased from trampling of the soil and drying out of the paddocks. Sheep grazed more of the medic pods than pigs. One batch of pigs was grown out over the period January-May. Performance was once again comparable with industry standards with daily weight gain of groups ranging from 573-763 g, back fat 7.5-11 mm and dressing percentage 76%. As a result of the mild summer conditions in South Australia in 2002 the performance of the poultry on the wheat stubble was excellent with production averaging 90%, in line with industry standards. Poultry foraged extensively in the wheat stubble throughout the foraging period (January-May 2002). After sheep had grazed the wheat paddocks there was an increase in the penetrometer readings in the paddocks. This reflects the trampling effect that sheep have on forage and soil with continued grazing whereas poultry paddocks showed no change in penetrometer readings. There was no effect of grazing on soil pH with this low stocking density of both sheep and poultry but soil nitrate levels were higher after grazing, suggesting that animal droppings were contributing to the increase. In the third year of the project poultry were allowed to forage on a regenerated medic pasture. Production of birds was comparable with the rate of lay recommended for this strain of birds in cages. However two fox attacks in the last 4 weeks of lay while birds were foraging during the day resulted in a sharp decline in production (15%) relative to the standard performance expected for these birds if housed in cages. In the poultry paddock soil fertility did not change during the growing season for the regenerated medic pasture. However penetrometer readings increased in the poultry paddocks as the soil dried out toward the end of the growing season of the pasture. This was also observed in the sheep paddocks where the increase in surface hardness was more apparent. There was a reduction in insect numbers before and after grazing in the poultry paddocks indicated by a related study examining the crop contents of birds foraging in the paddock. Insects consumed by the birds were observed in the crop together with seeds, grass, soil and small stones. Poultry appeared to have a preference for wheat, rye grass, other wild weeds, and other clover species and sour sob. However there was an increase in the amount of barley grass in the poultry paddocks. There was no difference in the sheep and chicken paddocks in the number of insects although after grazing the number of insects in all the zones was lower than the control zone. This shows that poultry have an ability to reduce insects by consuming them or acting as a deterrent for insects to habituate an area.

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Demonstration of a production system The main objective of this project was to demonstrate a free-range pig and poultry production system, which integrated with a traditional crop/pasture rotation system. This objective was achieved. Both pigs and poultry obtained feed resources from the paddocks and production performance of both pigs and poultry approached industry standards. The disappointing aspect was the fox attacks on poultry. The birds were locked up at night and this avoided any attacks except for the last month of the production trial. It is recommended in free-range systems that fences of sufficient height and strength be built to prevent foxes entering. This was not possible in this trial but in any future free range trials adequate protection for poultry is required. The fox attacks occurred during the day, which was not expected. In the pig system, electric fencing was used to keep pigs in their paddocks. This worked well, except for the first week of the trial with pigs tending to approach the fence and bolt through the fence when they received a light shock on their nose. As the pigs approached market age the mating activities in the pigs increased and on occasions this prevented some pigs obtaining their fair share of feed. Ecoshelters The shelters constructed were ideal for both pigs and poultry. Even under extreme weather conditions the shelters provided adequate protection from the element for the birds. The only concern was the very strong winds, which caused the blinds to flap loudly and driving rains, which sometimes entered the shelter. Utilisation of forage and control of weeds Both pigs and poultry were able to utilise the forage sources in the paddocks and grazed weeds. The stocking density used in the trial was very low. Use of a larger number of birds and/or pigs on pasture heavily infested with weeds offers an alternative approach to controlling weeds and avoiding the use of chemicals. The use of strip grazing to clean up weeds and moving the animals frequently to new areas is a strategy which could be employed particularly on farms where organic grain is being produced. The use of sheep with other species to selectively graze weeds and grasses has potential. The advantage of the low stocking density is that the production system is environmentally sustainable. Traditional free-range systems can cause environmental problems especially where land has been denuded and animals continually utilise the same area of land for extended periods. The use of animals in a cropping pasture system has considerable potential and the system established at Roseworthy attracted considerable interest. Most people were pleased to see the animals utilising the free-range facility and their perception was that it was a good system of production albeit with some of the problems that resulted many years ago in the commercial industry moving to intensive systems of production.

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Introduction In Australia, there is a great threat from the spread of weeds and diseases and a reduction in soil fertility in cropping areas. Weeds and diseases are costing the grain industry over $1.5 billion per year. To effectively control weeds, pest and diseases and improve soil fertility, farmers are using chemicals heavily. This has resulted in the resistance of weeds, pests and diseases, and the chemical contamination of farm products, which is a genuine concern for consumers. The industry needs a clean green cost-effective weed, pest and disease control program to improve farming profitability to meet the developing markets for chemical free produce. Recently, a commercial free-range pig production system has been successfully incorporated into a wheat-field pea cropping system in Tasmania, following the increased demand for free-range pig products by consumers opposed to intensive systems. The incorporation of free-range pigs into a cropping system was expected to assist in weed, pest and disease control in the crop phase, stabilise income (multiple enterprises); reduce chemical input; improve soil fertility and crop yield and change consumer perceptions. Consumers are also beginning to demand products from poultry in free-range production systems. Surveys of public attitudes indicate that free-range is given the highest rating as a production system. Under natural conditions in free-range the bird’s diet is a very mixed one-seeds, fruits, herbage and invertebrates and could achieve the reduction of problem insects and weed seeds. Free-range pig, egg and meat production is an emerging niche market in Australia. Incorporation of free-range pig and poultry into a cropping system using mobile shelters will have considerable public appeal. Opportunities also exist for using other species in the rotation eg. emus and ostriches. In addition it will provide supplementary income for farmers, reduce use of chemicals and improve soil fertility.

A major threat to the future viability of the organic produce industry is that returns are not maximised from markets which are now developing, as consumers move toward buying food products produced under clean green conditions where there is minimal use of chemicals. Due to the heavy use of chemicals under traditional farming systems it is important the organic industry align themselves with livestock production systems which offer the potential of producing products which fully utilise animal waste commodities. Potentially the Australian agricultural industry could receive a huge boost in farm income if products could be produced in more resilient farming systems where there is minimal use of chemicals used in improving fertility and controlling pests and weeds. Free-range pig and poultry farming gives the opportunity to develop integrated farming systems, where there is no chemical input but farm products are produced utilising the animal waste as fertiliser and using the pigs and poultry to control weeds and pests without the use of insecticides and weedicides. It is crucial that close attention be given by the organic industry to resolving the potential of utilizing previously used land where chemicals have been freely used and soil has been degraded by traditional farming practice. Utilising pigs and poultry in these areas on a small scale gives the opportunity to gradually rectify soil condition and eliminate weeds and pests, which have caused the over use of chemicals. Participation by industry in a research program to examine the potential benefits of adopting a new farming system to eliminate pests and weeds and avoid use of chemicals will achieve several benefits. It will establish new methods for improving farm income and place Australia as a country, which can lead the world in producing high quality organic produce in a resilient farming system. Free-range pigs Free-range pig production system is not new. This system has been adopted successfully in France. Legislation in Europe and the UK will soon prohibit the tethering and total confinement of farm animals (Henschke, 1998), and the increasing costs of establishing and maintaining conventional units, will result in more and more pigs being housed outdoors. In the Netherlands both breeding and fattening pigs (Janssen, et al., 1989) are common on free-range farms, with a clear emphasis on reducing production cost in the intensive system by adopting the free-range system (Voermans, 1998). For example in France, the number of free-range farms has increased from 209 in 1984 to 1608 in 1994 (Dagorn, et al. 1996).

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Apart from the higher quality pork production, the free-range pig production system appears to offer some solutions to many of the problems facing the Australian grains and pig industries. Research has demonstrated that free-range pig production system is as financially viable as the intensive system (Brownlow, et al. 1995). When comparisons were made of 2875 farms using the intensive system with 292 farms on a free-range system, Dagorn et al (1996) found no difference in litter size (live births) (9.7 vs 9.1), farrowing interval (152.9 vs 154.7) and lifetime number of litters per sow (4.7 vs 4.6). Echevarria et al. (1985) also reported a higher growth rate for pigs on oat pastures/sorghum grains than those on pure sorghum grain diet (429 vs 547 g/day). Allowing pigs to forage on pasture was particularly suited to the pigs' natural behaviour and also improved carcass composition and health (Stoll and Hilfiker, 1995).

The free-range pig production system in Australia has generally been left to either specialist enthusiasts or low input/low output operations. The more progressive free-range producers have adopted practices from the UK. Experience in Tasmania with free-range pigs, compared with intensive production system, suggests no additional health problems, particularly with regard to pneumonia. In fact, free-range pigs have a reputation for robustness and ease of adaptation to new environments (Riley 1993; Terry 1993) It is envisaged that the incorporation of free-range pigs into the crop-pasture rotation system will improve the soil fertility, break root disease of crop and pastures, and consequently improve crop yield and quality. More importantly, this system could increase the income of the enterprise compared with the current crop-pasture-sheep production system due to the high price of pork, especially free-range pork. While there have been no attempts to integrate free-range pigs into the crop/pasture rotation system, Terry (1993) has 900 sows with cattle, and sheep in his rotation system. Because of the positive welfare and financial aspects of free-range pig production system and the customer's demand for a greener and chemical free product, there is a need to evaluate the traditional farming methods to produce a product meeting the demand of the consumer. Free-range Poultry Small scale operations in which hens, ducks or geese wander freely during the day is widespread on farms and rural properties. In Australia there are grain farmers, market gardeners and graziers who practice free-range poultry farming. This is the only true free-range system, in that bird are unrestricted in their movements except that they are usually shut up at night for protection from predators. Consumers pay a premium on the grounds of enhanced welfare and for the eggs, which are perceived as having superior taste and nutritional properties. Free-range poultry meat can also command a premium. This market is in its infancy but current indications suggest that free-range meat production will expand much like free-range egg production. Fixed housing is rarely used in free-range operations, with the most popular system being the use of moveable shelters and birds provided an area of pasture in a rotation system. Birds, which go onto a pasture from a free-range house generally, move as a flock. Under natural conditions the fowl’s diet is a very mixed one-seeds, fruits, herbage and invertebrates. It browses on the herbage and forages by scratching at the ground exposing small food items, which are consumed. When available birds consume berries and seeds, figs, leaves, isopods and insects (McBride et al., 1969). Juvenile birds food consists mainly of invertebrates because as growing birds they require a high protein diet, while adults in the main, eat cereals in the autumn and winter and grass and herbage in the spring and summer (Savory et al., 1978). Most bird species will consume animal food in the first two weeks of life whereas by 8 weeks of age most bird species will subsist on mainly plant material (Savory, 1989). Medium hybrid hens in small flocks on free-range with access to mash feed eat at least 50 g of dry matter pasture/day (Hughes and Don, 1983). Under free-range conditions birds are capable of selecting a diet which is adequate for all their requirements (Hughes, 1984). Under free-range conditions foraging occupies 7-25 % of the birds time (Appleby et al., 1989). It is during this period that birds have a great potential to consume weed seeds and pests, which would be of great benefit in a crop/animal rotation system. However, there have been no attempts to integrate

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poultry into conventional wheat/pasture rotation systems. While it is not expected that poultry would be dominating the sheep/wheat areas in Australia, there is a definite potential for farmers to establish niche markets free-range eggs and chicken meat and organic wheat. In Australia there are grain farmers, market gardeners and graziers who practice free-range poultry farming and attempt to avoid use of chemicals in their operations. Overall in Australia up to 10 % of eggs are produced in floor based systems with an increasing trend for birds to be run in the free-range system. Surveys of public attitudes indicate that free-range is given the highest rating as a production system and consumers are prepared to pay more for the products produced in these systems.

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Literature Review The literature available on free-range pig and poultry production systems is extensive. Literature reviews were undertaken for pig and poultry free-range systems, to identify the main management, nutritional, product quality, and disease and sustainability issues of concern. Free-range poultry production-a review Abstract With the demand for free-range products increasing and the pressure on the intensive poultry industry to improve poultry welfare in western countries, the number of free-range poultry farms has increased significantly. The USA, Australia and European countries have developed Codes of Practice for free-range poultry farming which detail the minimum standards of husbandry and welfare for birds. However, the performance and liveability of free-range birds needs to be improved and more knowledge is required on bird husbandry, feed supply, disease control and heat wave management. This review summarises the husbandry, welfare, nutrition and disease research conducted on free-range poultry systems and discusses the potential of incorporating free-range poultry into a crop-pasture rotation system. Keywords: Forage, Nutrient Requirement, Poultry Husbandry, Animal Welfare, Free-range egg, Free-range meat Introduction There has been a resurgence of interest in free-range poultry farming in recent years in developed countries, as a result of welfare concerns associated with farming of poultry under intensive conditions. For the “best positive welfare outcome”, birds should be free from hunger, thirst, discomfort, pain, injury, disease, fear and distress and able to express normal behaviours (Brambell, 1965). On the basis of these requirements, the Agricultural Committee of the Swedish Parliament defined the following four criteria for free-range birds: 1) animal health should not be worse, 2) the use of medication and chemicals should not increase, 3) the environment should not be impaired and 4) beak trimming should not be necessary (Sorensen, 1994). However, the Swedish model did not give any weight to the cost of production. Instead the top priority in assessing and comparing production systems was welfare. Stewart (2002) suggested that two more criteria should be added to the above list; 1) the natural environment be enhanced or protected and 2) product quality be maintained or enhanced. Based on these welfare criteria, the free-range system is considered the most acceptable housing system for poultry. Under free-range conditions, the birds show high vigour, a firm and strong feather coverage, warm red combs and wattles (Bogdanov, 1997). Birds show typical signs of calmness and comfort, such as dust and solar bathing, stretching wings and beak cleaning and preening (Bogdanov, 1997). Today, free-range is a specific term. European Union regulations demand that eggs offered for sale as free-range must be from flocks that are kept in the following conditions:

1. The hens must have continuous daytime access to open-air runs. 2. The ground to which hens have access must be mainly covered with vegetation. 3. The maximum stocking should not exceed 1000 birds/hectare (400 birds/acre, or 1 bird/10

m2). 4. The interior of the building must conform to one of the following standards:

• Perchery (barn) - where there is a minimum of 15 cm perch space per bird and a maximum stocking density of 25 birds/m2 in the building.

• Deep litter - where at least one-third of the floor area is covered with litter such as straw, wood shavings, sand or turf, and a sufficiently large part of the floor area is available to

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the hens for the collection of bird droppings. The stocking density should not exceed 7 birds/ m2 of available floor space (Thear, 1997).

Another factor resulting in resurgence in free-range poultry production worldwide is the demand by consumers for free-range products. For example in Australia it is estimated that free-range production systems account for about 6-8 % of total egg production and 10-12 % of supermarket shell egg sales in Australia (McMaster, 1999). The average commercial free-range flock consists of 1000-2000 hens. Consumers have the perception that free-range eggs are a healthy and wholesome food, low in calories and saturated fats, high in protein and vitamins. Many consumers are prepared to pay an increased price for such a product because of the higher cost of production associated with the greater land area required, increased labour output per bird, higher feed consumption and poor economies of scale in grading, packaging and distribution as compared to the cage industry. The following review was undertaken to obtain information on free-range production systems, in particular to identify the main management, nutritional, product quality and disease issues of concern in free-range farming. Housing for Free-Range Poultry Free-range farmers generally use either barns or aviaries for housing with access for the birds to the range through pop-holes, either directly or through an enclosed verandah. The free-range area can be accessed directly or via a walkway to the end of the shed to access paddocks. The pop-holes can be shut in the evening. Water is generally available outdoors. Alternatively a single pop-hole with bars, to exclude foxes, may be left open to minimise the need for after-hours labour. To minimize the amount of dirt carried back into the sheds a number of farms have wire mesh grates in front of the pop-holes. To prevent the area around sheds becoming muddy from excess bird activity, a large number of farms also have some removable material (small rocks, gravel, wood chips, wood shavings) along the length of the shed sides for about 5-10 metres away from the shed. Both fixed and mobile shedding are common used in free-range systems. In Australia the sheds are open-sided with ventilation provided by adjustable blinds. The fixed sheds have litter, perches and nest boxes (either manual or automated). Paddock rotation is not routinely practised although some farms provide rotation by using electric fences. Barnett (2001) reported that mobile sheds are used in some regions of Victoria. These house from 100-500 birds and stand on a moveable sled and are towed to positions around a paddock once or twice a week. Wire floors enable droppings to fertilise the area. These sheds are generally used by grain farmers between crops. Additional light is generally not provided. Breeds for Free-Range Production The ideal free-range egg layer should have adequate body weight at the start of lay and a good hen-housed egg production (Thear, 1997). More importantly these birds should reproduce and survive under very harsh environmental conditions (Huque, 1999). Modern strains can be successfully raised in free-range conditions with a slightly lower rate of lay during summer (Glatz and Ru, 2002). Local breeds are inseparable from the rural scenario due to their adaptability under harsh environmental conditions. However, local breeds have a low egg production and slow growth rate. Apart from these limitations, there is a good market for both meat and eggs from local breeds in both the European Union (EU) and Asia. Selection of the breeds that are more resistant to the disease is another important strategy for free-range production. Permin and Ranvig (2001) compared the resistance to Ascaridia galli infections between Lohman Brown and Danish Landrace strains of poultry. A self-cure mechanism to A. galli infections was observed in both breeds. However, significantly higher worm burdens and egg excretion was found in the Danish Landrace compared to Lohman Brown poultry during primary infection. This suggests that breeding and selection of strains for resistance to diseases for free-range poultry production is possible.

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Apart from the crossbreeding of local and improved strains, on-going selection and breeding for free-range production is required. Birds for free-range production should have a better feed conversion, strong plumage and insusceptibility to stress. The selection against insusceptibility to stress and feather pecking are part of a breeding program, requiring data recording and selection to be carried out in an environment that resembles the production environment as closely as possible to minimise the risk of selection errors due to genotype and environment interactions. To improve egg number, shell colour and strength, the proven testing procedures established for all commercial lines are used throughout and implemented in the selection process. Optimising feed intake and egg mass output in the first third of the production cycle are the most critical trait combination in selecting birds for organic free-range farming (Preisinger, 2001). Free-Range Poultry Management

The management of free-range birds is labour intensive and very complex due to the uncontrolled environmental conditions and unpredictable diet composition. For example, the optimum temperature for a layer is 21°C, but it is impossible to maintain this optimum temperature under free-range condition. The free-range birds forage pasture and are attracted to insects. Birds foraged mainly within 30-40m of the shelter but also foraged further out into the paddock especially when attendants were present (Glatz and Ru, 2001, 2002). For free-range birds, trees around the paddock offer protection for foraging birds from sunburn as well as predators and often the birds range much further in the field (Thear, 1997). The fluctuation in temperature often affects the egg production of layers. As ambient temperature declines, feed intake increases as the free-range layer consumes more energy to maintain body temperature (Portsmouth, 2000). It was also reported that in winter, for every 1°C fall in temperature from the optimum, a laying bird needs an extra 1 Joule (Thear, 1997). However, in summer, especially under a Mediterranean environment, high temperature is one of the key factors limiting free-range production. As temperature increases, egg weight and shell thickness are reduced (Payne, 1966, Mowbray and Sykes, 1971, Warren and Schnepel, 1940) due to a reduction in energy and protein intake (Emmans, 1974, Cowan and Michie, 1977). Mowbray and Sykes (1971) found that egg production could be maintained at the same rate as that achieved by normally housed control birds when the air temperature was kept at 30ºC constantly, or cycled from 30ºC to 18ºC or from 35ºC to 13ºC (10 hours at the higher temperature in each case). Drinking water temperature: Glatz (2001) recommends that water temperature for free-range birds should be monitored, particularly in hot weather. On free-range farms, hens should be provided cool water, particularly in hot weather. This can be achieved by regularly flushing the drinker lines, keeping incoming water lines out of direct sunlight, insulating water lines and ensuring water storage tanks are shaded. Adding ice to the header tank is another effective way of reducing water temperature in hot weather. A more expensive option is to install an external water-cooling unit to maintain incoming water below 30°C during heat waves, as water intake is reduced above this temperature. If water is too hot, birds will drink less, which will result in reduced feed intake, egg production and poorer shell quality (Glatz, 2001). During heat waves birds may not be able to keep cool in the shelter. To overcome this problem foggers can be used in shaded areas or in trees. Other options in sheds include the use of insulation on roofs, sprinklers on roofs and use of fans to increase air movement around the birds. The Australian Code of Practice (SCARM, 1995) states that the free-range housing facility must be designed to ensure adequate airflow and temperature control at maximum stocking densities when birds cluster or perch at night or during extreme weather conditions. Orientation and spacing of buildings is another important consideration to reduce the overall heat load. Planting trees around the facility also provides shade on buildings and reduces the heat load. Stocking density: Another factor requiring consideration when establishing shelters for free-range birds is density, especially in the shelter. The effect of stocking density on egg production has been

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well demonstrated. For example, the rate of lay can be depressed by 5 to 7% at 15 birds/m2 compared with 7.5 birds/m2 (Hill, 1985). The Code of Practice in most countries offers guidelines for free-range farmers on maximum stocking densities allowed. For example in Australia the Code of Practice recommends a maximum of 30 kilogram of bird/m2 of available space indoors and no more than 1500 hens/hectare (SCARM, 1995). In Victoria, Australia the Free-range Egg Producers Association (FREPA, 1998) recommend a maximum stocking density of 750 birds/hectare. The UK Soil Association requires that the stocking rates should not exceed 250 birds/acre (625 birds/hectare) (Thear, 1997). Nest boxes: In a small shelter, nest boxes need to be placed lower than the perches and in the darkest area of the shelter to attract the poultry to select their nest and discourage egg eating. Nest boxes should be above ground level to avoid floor-laid eggs; a common problem for free-range poultry. Loose material in the nest boxing is preferred by poultry. Thear (1997) suggested that straw is better than hay as it becomes mouldy, leading to respiratory problems in both birds and farming staff. The Australian Code of Practice (SCARM, 1995) recommends 7 birds/nest box. Shell grit is often used in nest boxes to ensure free-range birds obtain sufficient calcium and also to prevent development of respiratory problems. Rotation: Production by free-range poultry is constrained by disease due to the accumulation of parasites and other pathogens in the paddock, especially when the birds have been housed and forage in the same paddock for a long period. Currently the recommendation to the free-range industry is to rotate the flock between paddocks. This rotation system reduces the danger of endoparasites, including coccidiosis (Folsch et al., 1988). Some farms utilise one paddock at a time for a 12-week period before rotating to the next paddock. The incorporation of free-range poultry into a cropping system will be expected to assist in weed, pest and disease control in the crop phase, stabilise income (multiple enterprises), reduce chemical input, improve soil fertility and crop yield and change consumer perceptions. Glatz and Ru (2002) assessed the potential of using free-range poultry in a crop/pasture rotation system where free-range poultry were compared to sheep. In this study, Merino wethers were stocked at a rate of 6 sheep/paddock (0.5 hectares) giving almost twice the stocking rate of poultry when assessed on a kilogram/hectare basis. The availability of pastures, weed and insect population was monitored during the season. The herbage availability was greater in the chicken paddock than in the sheep paddocks after 3 months of foraging (Table 1). Sheep grazed the medic pods heavily leaving only 30g/m2 of pods while poultry left 965g/m2. The paddocks foraged by free-range birds did not need to be re sown with medics for the next pasture season given the high abundance of seeds. The snail population in this trial at the time of sampling was low probably as a result of the dry weather conditions at the time of sampling. Likewise very few insects were also observed at the time of sampling. Sheep, however, were very effective in grazing the wire weed, which contaminated the paddocks whereas poultry avoided this weed. In contrast, the number of unidentified weeds in the sheep paddock was greater than the poultry paddock. This raises the possibility that sheep and poultry could be grazed together in some circumstances, to provide a method for reducing weed build up, using sheep to graze out weeds they prefer and poultry to consume weed seeds that sheep avoid. Soil fertility was not different between the sheep and poultry paddocks.

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Table 1. Comparison of the agronomic, snail, weed and soil fertility in paddocks grazed by sheep and poultry (Glatz and Ru, 2002).

Variable Poultry Sheep P Biomass (g/m2) 491 132 *** Dry matter (g/m2) 417 109 ** Crude protein (g/m2) 50 6 ** Organic matter (g/m2) 374 91 ** Snails (no./m2) 4 2 NS Medic pods (no./m2) 418 69 ** Wire weed (no./m2) 23 0 ** Unidentified weeds (no./m2) 5 16 *** Nitrate N (mg/kg soil) 18 24 NS Ammonia N (mg/kg soil) 0 0.1 NS

***, significantly different at P<0.01; **, different at P<0.05; NS, not significant Beak trimming: Taking birds out of cages increases cannibalism (Wills, 2002). Although the free-range system enables the bird to have greater freedom to express natural behaviour, vices such as feather pecking, cannibalism and mislaid eggs continue to be a problem in free-range (Keeling et al., 1988 and Fiks-van Niekerk, 2001). A survey of Dutch organic farms with laying hens showed that 50% of the flocks have severe problems with cannibalism, 25% with moderate problems and only 25% have no or few problems with feather pecking (Bestman, 2000 reported by Fiks van-Niekerk, 2001). Feather pecking and cannibalism are more prevalent with a large group size; also the presence of males has been an important factor in reducing this behavioural problem in females. A comparison of the management and husbandry of 112 free-range flocks in the UK revealed that feather pecking was greatest when a low percentage of the flock used the outside range (Thear, 1997). Beak trimming is necessary to stop feather pecking and cannibalism under free-range conditions, especially when birds are overcrowded in the shelters (Thear, 1997). This has the result of increasing the stocking density within the house increasing the bird to bird interactions (Nicol, et al., 2001). The use of plastic slats in the house reduces risk of feather pecking. The Shaver bird has a low propensity to use the outside range area. Farmers are generally reluctant to try and increase range use, although they are receptive to other management changes, like litter condition, diet and reducing the use of bell type drinkers (Green, et al., 2000). However, apart from animal welfare consideration, the impact of beak trimming on foraging ability of free-range birds needs to be assessed. Poor beak trimming often results in hens with poor beak condition (bubble beaks, split beaks and short beaks) and these birds are likely to have difficulty in foraging or feeding especially on free choice diets where particle size of the ingredients varies greatly (Glatz, 2000 and Glatz, 2003). Feeding Free-Range Poultry Under natural conditions the fowl’s diet is a very mixed one, comprising seeds, fruits, herbage and invertebrates (McBride et al., 1969). The bird browses on the herbage and forages by scratching at the ground exposing small food items. Juvenile birds’ food consists mainly of invertebrates because growing birds require a high protein diet, while adults consume cereals in the autumn and winter and grass and herbage in the spring and summer (Savory et al., 1978). Most bird species will consume animal food in the first two weeks of life whereas by 8 weeks of age most bird species will subsist on mainly plant material (Savory, 1989). Under free-range conditions birds are capable of selecting a diet that is adequate for all their requirements (Hughes, 1984). With foraging occupying 7-25 % of the birds time (Appleby et al., 1989), birds have a great potential to consume weed seeds and pests, which would be of great benefit in a crop/animal rotation system. However a factor which might contribute to poor performance is toxic plants and seeds on the range. Problem plants include vetch, phalaris, heliotrope and amsyncia (yellow ironweed). According to the Australian Code of Practice (SCARM,

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1995), poultry should not be kept on land which has become contaminated with poisonous plants. A large amount of information on nutrient requirements is available for various strains of birds under intensive housing system. For example, NRC (1994) recommended nutritional specifications for layers and broilers at different growing stages. However, the foraging activity and variable environmental conditions of free-range poultry makes it hard to apply the nutritional management guidelines recommended for intensive birds. More importantly, local breeds in Asian countries are widely used in free-range poultry production systems, with very limited knowledge of nutrient requirements of these breeds, although it is well known that the nutrient requirement is higher for free-range birds than those housed intensively. Theoretically, the amount of feed offered to foraging birds should be the amount of feed required minus the intake from foraging. The amount of feed required changes with season and ranging conditions such as the cost of energy for maintaining body temperature in winter. High temperature in summer often reduces the intake, consequently rate of lay and egg size. Increasing nutrient density (amino acids and essential fatty acids) in supplementary feed can increase the nutrient intake (Portsmouth, 2000). The amount and type of nutrients foraged by free-range birds is a mystery, which limits the capability of nutritionists to formulate supplementary diets to maintain high production and egg size. Hughes and Dun (1983) reported that medium hybrid hens in small flocks on free-range with access to mash feed eat at least 50 g of dry matter pasture/day, but the actual nutrients ingested depends on the diet composition which is influenced by the type of crop, pastures, weeds and insects available in the paddock. The amount of feed available for foraging in relation to the carrying capacity of the land areas and flock dynamics across the different seasons and agro-ecologies has not been quantified. A study in Ethiopia revealed that the materials present in the crop were seeds, plant materials, worms, insects and unidentified materials (Table 2 and 3) (Tadelle and Ogle, 2000). During the short rainy season, the percentage of seeds in the crop content was higher due to the increased availability of cereal grains and low availability of plant materials. There were more vegetative plant materials in the crop content during the rainy season because of the increased availability of plant materials, especially the green shoots that are palatable to the birds. However, the largest proportion of worms and insects in the crop contents were found during the rainy season. The energy and protein supplied from the forage resources, as determined from chemical analyses of crop contents, were 11.97 MJ/kg and 8.8%, respectively (Table 4). The protein content was even lower during the short rainy and dry seasons, while the energy supply was more critical in the drier months (Tadelle and Ogle, 2002). These values were below the protein requirement of free ranging local hens in the tropics, estimated at about 11 g/bird/day, and the ME supply could only meet the requirement of a non-laying hen (Scott et al., 1982), indicating limitations of the foraging feed resources in terms of nutrient supply to increased productivity Table 2. Effect of season on crop contents of scavenging local hens (physical observation) (Tadelle and Ogle, 2000)

Season No. of birds Physical components (% fresh basis) Seeds Plants Worms Insects Others

Short rainy 90 37.5 22.5 2.6 14.6 22.7 Rainy 90 25.8 31.8 11.2 7.7 23.4 Dry 90 29.5 27.7 6.2 11.1 25.6 Means ±se 270 30.9±7.9 23.3±6.0 6.7±4.5 11.1±4.5 23.9±4.6

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Table 3. Effect of altitude on crop contents of scavenging local hens (physical observation) (Tadelle and Ogle, 2000) Season No. of

birds Altitude (m) Physical components (% fresh basis)

Seeds Plants Worms Insects Others High 90 2780 33.2 28.2 9.0 8.8 20.8 Medium 90 1850 32.0 27.9 5.9 11.5 22.7 Low 90 1550 27.7 25.8 5.1 13.1 28.3 Means ±se

270 31.0±3.6 27.4±0.8 6.8±2.2 11.2±2.3 23.6±3.4

Table 4. Chemical composition of the crop contents of scavenging hens, overall means, SD and range from three of the seasons and study sites (Tadelle and Ogle, 2000) Chemical composition (%) Means±SD (270) Range (270) Dry matter (DM) 50.7±12.5 26.4-85.8

As % of dry matter Crude protein (CP) 8.8±2.3 4.3-15.4 Crude fibre (CF) 10.2±1.6 6.5-14.0 Ether extract (EE) 1.9±0.9 0.3-4.7 Ash 7.8±2.7 1.6-15.7 Calcium (Ca) 0.9±0.4 0.2-1.9 Phosphorus (P) 0.6±0.3 0.1-2.4 Energy (ME, Kcal/kg calculated) 2864.3±247 2245.1-3528.1 While an understanding of the seasonal forage intake of free-range birds is essential for developing effective supplementary feeding strategies, it is difficult to measure the intake of foraging birds due to the lack of an appropriate method. While the visual separation of crop contents can give some guidelines on the diet composition, it cannot be used to further quantify the pasture species ingested by birds. Measuring the availability and botanic composition of pastures pre- and post foraging might indicate the preference of foraging birds over pasture species, but the result is influenced by the sampling method, regrowth of pastures and patchy foraging. Currently a method using plant alkanes as a marker has been developed to measuring forage intake of grazing sheep (Dove and Mayes, 1991) and deer (Ru et al., 2002). N-Alkanes are long-chain (C25-35) hydrocarbons, predominantly with odd-numbered carbon chains, which occur in the cuticular wax of most plant material including cereal straws. Dove and Moore (1995) showed that the species composition of the herbivore diet could be estimated from the pattern of alkanes in each diet component and the faeces of the animal consuming them. If pigs or chicken are dosed orally with synthetic even-chain alkanes, total intake and whole diet digestibility can be calculated. This provides information about total intake, the intake of different diet components and their effects on whole diet digestibility, in relatively undisturbed animals. This technique can then be used to assess other factors that may influence feed intake. Fundamental to the use of n-alkanes to measure feed intake and diet composition of monogastrics is recovery of the marker from the faeces and consistent passage through the digestive tract. Choct and van Barneveld (1995) demonstrated total recovery of n-hexatriacontane relative to acid-insoluble ash in both ileal and faecal samples of pigs fed diets containing lupins (and hence high levels of dietary fibre) included at levels of 0, 12, 24 and 36%. Dove and Mayes (1991) also cited evidence that hydrocarbons are not utilized or metabolized in monogastric species. Wilson et al. (1999) demonstrated that recoveries of n-alkanes were consistent in pigs, did not vary systematically with increasing chain length of the alkane and were unaffected by dietary lipid content. More importantly, if only diet composition and digestibility are concerned, there is no need to dose synthetic even-chain alkanes to animals. However, this method needs to be developed and validated for measuring intake and diet composition of free-range birds.

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Generally, the supplementary feed should be fed outside, in a different area every day to encourage birds to forage. This is a biosecurity concern as it also provides food for wild birds which could be a source of disease (Thear, 1997). The feeding time could vary, depending on the objectives. Feeding birds in the morning outside the shelters encourages birds to forage further, but feeding birds in the afternoon in the shelter assists in getting birds back from the paddock. Bogdanov (1997) fed 150g of cereals (wheat, corn and barley) plus 30 g/hen fresh sliced nettle in late afternoon and obtained a good laying rate (57%) for 164 days. The egg quality (normal shells, firm egg whites and yolk colour) was ideal, despite the imperfect diet. The contribution of insects, seeds and other materials to nutrient requirement of birds is significant, but the contribution of hindgut fermentation of fibrous materials to the energy requirement of birds is not clear. Most researchers believe that the energy produced by hindgut cannot be used by poultry even though Kass et al. (1980) reported that VFA produced in the large intestine of pigs can provide up to 6.9, 11.3, 12.5 and 12.0% of energy required for maintenance in the 48 kg pigs, respectively when fed 0, 20, 40 and 60% lucerne meal in the diets. However, the extent of hindgut fermentation is much less for poultry than pigs. Biobalanced feed management systems have been developed to decrease the costs of feed for free-range poultry. This system uses the biological processes to improve the balance between the environment (especially the feed) and the bird, and between the bird (especially its excreta) and the environment. A diet made of pure nutrients mixed in the quantities required by the bird with no waste would be a perfectly biobalanced feed without environmental pollution, but it would not economic if cheaper resources are available. The objectives of this feed management system is to reduce wastage and to provide only enough nutrients for the animal’s use for maintenance and production. The reduction of the waste of resources is achieved by 1) decreasing the level of all nutrients in the diet, especially protein; 2) formulating diets to contain just the level of nutrients required by the stock by using neutral ingredients, but no supplement or premixes, and 3) assuming that free-range birds can get enough vitamins and minerals from green feed, faeces and soils. Apart from using the locally available cheaper feed resources, this system also 1) saves the cost on feed by not processing feedstuffs (e.g. grinding, mixing, pelleting) (Dingle and Henuk, 2002), 2) increases the digestibility of nutrients and decreases the amount of waste excreted by a) adding enzymes to the feed, such as phytase to reduce P output; b) Using prebiotics and probiotics to condition the gut to more readily absorb nutrients and avoid the use of antibiotics, and to decrease the nutrient partitioning that may be the reason for low productivity and c) encourages caecal fermentation so that more B vitamins are produced there (Dingle and Henuk, 2002). Feeding chicks: The utilisation of fat is poor for chicks in the first week of age. Application of vegetable oils such as soybean or canola oil has limited value. The inclusion of palm oil and animal fats in the diet can limit the uptake of essential elements (e.g. Ca, P) and many of the trace elements due to the formation of insoluble soaps with minerals. The diet in the first few weeks should be palatable and rich in digestible carbohydrates. Maize is a good source of carbohydrate, but is not a common ingredient in the poultry diets in Australia. Wheat is used in most situations in Australia, especially in conjunction with enzymes (e. g. xylanase). Grit should be available in the paddock to stimulate early gizzard development (Portsmouth, 2000). The diet specification recommended by Portsmouth (2000) for free-range birds is listed in Table 5.

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Table 5. Chick starter and pre-lay feed specifications (Portsmouth, 2000) Nutrient Chick starter specification Pre-lay specification Protein % 20-21 16-17 ME (MJ/kg) 12.0 11.5 Lysine (total) % 1.15 0.75 Lysine (avail.) % 0.99 0.65 Methionine (total) % 0.50 0.34 Methionine (avail.) % 0.45 0.31 Methionine + Cystine % 0.83 0.60 Tryptophan % 0.20 0.17 Threonine % 0.73 0.50 Calcium % 0.90 2.0 Avail. Phosphorous % 0.45 0.40 Sodium % 0.20 0.16 Linoleic acid % 1.25 1.25 Added fat/oil Optional 2-3%

The growing stage: The energy level in the diet is critical during the post chick feeding stage, particularly in the period from ten weeks to the start of lay. Maintaining optimum stocking density is important to ensure that all birds have access to feeders and drinkers to avoid uneven growth. Low energy diets from 6 to 15 weeks should be avoided. The inclusion of enzymes in the free-range poultry ration could improve the energy utilisation efficiency, especially when a large amount of fibre is consumed by birds foraging pastures. Pre-lay to early lay: This is a very critical period and many free-range flocks are held back by poor pre-lay nutrition. The requirements for pre-lay are listed in Table 5. Calcium is important for the development of medullary bone, but only 2% is recommended for the pre-lay diet (Portsmouth, 2000). It was found that increasing Ca to 3 % in the pre-lay diet did not enhance bone development and an excessive amount of calcium can have a negative effect on feed intake. Oyster shell is better Ca source than limestone granules because the rate of limestone going into solution is too rapid to sustain blood calcium levels over long periods (Bogdanov, 1997; Portsmouth, 2000). Disease Control Mortality is high for free-range poultry in comparison with intensively housed birds (Maphosa et al., 2002), especially during the first 6 to 8 weeks of life (Rodriguez, 2002). One of the major reasons for high mortality is disease. Free-range poultry and their eggs are more likely to be infected by virus and parasites than caged birds and their eggs. These poultry are susceptible to the same metabolic diseases affecting intensively kept birds, but the environment can influence their severity and make the birds susceptible to syndromes rarely found in caged layers (Mostert et al., 1995). Pennycott and Steel (2001) surveyed 27 sites in England and Wales for endoparasites and found 43% per cent of flocks were positive at 20 weeks of age, 62 % were positive at 33 weeks of age, 79% at 46 weeks of age, and 81% at 59 weeks of age. In this survey, 13 flocks were not wormed at all during lay, and the results from these flocks demonstrated a similar pattern. Overall 38%, 46%, 77%, 92% of flocks were positive for worm eggs at the week 20, 33, 46 and 59 respectively (Portsmouth, 2000). Martin (1999) also found that viral infections present in the free-range poultry population in Tokelau included infectious bronchitis, infectious bursal disease, infectious laryngotracheitis and Marek's disease. A prevalence study of gastrointestinal helminths in Danish poultry production systems also confirmed the high risk of helminth infections in the free-range system (Permin et al., 1999, Table 6).

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Table 6. Sample size, prevalence of gastrointestinal helminth infections in Danish poultry (Permin et al., 1999) Helminths

Free-range/organic

(n=69)

Deep-litter (n=62)

Battery cages

(n=60)

Parents (broiler) (n=61)

Backyard (n=16)

Farm sampled 4 4 4 4 16 Ascaridia galli 63.8* 41.9 5.0 - 37.5 Heterakis gallinarum 72.5 19.4* - - 68.8 Capillaria obsignata 53.6 51.6 - 1.6** 50.0 Capillaria anatis 31.9 - - - 56.3 Capillaria caudinflata

1.5 - - - 6.3

Cestode+ - - 3.3 - 0 N =number of animals examined, - no helminths identified, + Cestodes were either the Raillietina cesticillus or Choanotaenia infundibulum, * significantly different compared to other systems (P<0.05), ** significantly different compared to other systems (P<0.01). There is a difference in the prevalence of ecto-, endo- and haemoparasites between sexes/ages of free-range poultry. A study conducted in Zimbabwe showed all poultry harboured ecto- and endoparasites, and 32% were infected with haemoparasites (Permin et al., 2002). The prevalences of Cnemidocoptes mutans, Goniocotes gallinae and Menopon gallinae were higher in adults compared to young poultry. The young poultry had a higher prevalence of Ascaridia galli and Raillietina echinobothrida compared to adults, but lower prevalence of Gongylonema ingluvicola and Skrjabinia cesticillus. A similar result was reported by Magwisha et al., (2001). It is also clear that the sex of the poultry can influence the burdens of Heterakis brevispiculum. Dahl et al. (2002) found an interaction effect such that growing males and adult females had statistically higher (p<0.05) burdens of T. tenuis and A. suctoria, respectively. Diseases can be transmitted to free-range poultry by old flocks, wild birds, drinking water in the paddock and predators, and is hard to control. To offer maximum protection to free-range birds, all relevant and available vaccines should be used. These include Infectious Bronchitis, Newcastle Disease, Egg Drop Syndrome (carried by wild ducks into water), Infectious Larngotracheitis, Cholera (Pasteurella infection, carried by wild ducks), Coryza, Marek's disease, Fowl Pox (carried by mosquitos in certain areas of Australia) (Wills, 2002). Other strategies include 1) the frequent rotation of the free-range birds before the build up of parasites, 2) keeping the new birds separate from older ones (Thear, 1997) and 3) rearing chicks in confinement for the first 8 weeks of age. For the latter, the question is whether this rearing system influences the learning capability of chicks from mother hens on how to scavenge and survive in a harsh environment, although there is no clear understanding of the degree of inheritance for scavenging traits (Rodriguez, 2002). Malnutrition of the host might influence the population dynamics of parasites in the gastrointestinal tract (Bundy and Golden, 1987 and Michael and Bundy, 1991). Bundy and Golden (1987) suggested 3 major mechanisms whereby the nutritional status of the host might influence the helminth parasites, including 1) a change in the host immune system mediated by nutrition, 2) malnutrition of the helminths and 3) changes in the gut environment caused by diet. Their research also showed that the extent of parasitism increases as a result of an immunosuppressive effect caused by malnutrition in the host. The research by Permin et al. (1998) indicated that the amount of protein in the diet might have an effect on the establishment of A. galli infections in the gut of laying hens under free-range conditions. Raising the protein content from 14% to 18%, without changing other parameters of the diet increased the mean worm burden from 7.2 to 11.5. These differences might arise from the nutritional requirements of A. galli. A moderate decrease in the protein content of the diet resulted in a significantly lower number of adult worms in the gut, but did not affect the egg production. While the application of antibiotics can control diseases effectively for free-range poultry, the wide spread use of antibiotics may lead to the emergence of resistant bacterial populations in poultry and other animal species. Ojeniyi (1985) examined the sensitivity of E. coli strains isolated from

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commercial battery poultry and free-range poultry in Nigeria. It was found that all E. coli strains from free-range poultry were sensitive to dugs tested except for tetracycline, while all the E. coli strains isolated from battery poultry were resistant to most of the drugs tested (Table 7). Table 7. Drug sensitivity tests on 1248 E coli strains isolated from university battery poultry, 2196 strains from commercial battery poultry, 1220 strains from free-range town poultry and 1064 strains from village poultry in tropics (Ojeniyi, 1985) % resistant A (n=1248) B (n=2196) C (n=1064) D (n=1220) Colistin 2 2 0 0 Nitrofurantoin 2 2 0 0 Nalidixic acid 0 0 0 0 Ampicillin 22 24 0 0 Chloramphenicol 11 12 0 0 Streptomycin 100 100 0 0 Sulphonamide 100 100 0 0 Tetracycline 100 100 4 6 A: E coli isolates from university modern battery poultry B: E coli isolates from commercial farm battery poultry C: E coli isolates from free-range town poultry D: E coli isolates from village poultry Performance of Free-Range Poultry

Generally, the free-range poultry production system is characterised by low productivity and low input. The productivity is dependent on the genetics of the stock, the effectiveness of disease control, the quality of supplementary feeds and the availability of pastures. It has been reported that egg production fluctuates with season under the free-range system because the egg laying mechanism is controlled by hormones that are produced by the action of the pituitary gland in the brain (Manser, 1996). This, in turn, responds to the amount of light falling on the birds' eyes. As less daylight is available, the pituitary gland is influenced in such a way to reduce hormonal action, and ultimately egg production. The number of eggs is gradually reduced until laying ceases. While extra light can be supplied in the shelters at night for free-range poultry, the following rules should be followed.

• Do not provide extra light too early, before point of lay pullets have grown adequately, or they will lay early and the eggs will be small. They may also have problems of coping with laying large eggs later if they are young.

• Increase the period of light gradually until the maximum of 15-16 hours reached. • Do not allow the day length to shorten once the birds are laying (Thear, 1997).

In most situations, the free-range system houses about 500-7000 birds. The feed intake is about 120 g/day, and egg production about 270 eggs per year, equivalent to 75% of rate of lay (Folsch et al., 1988). However, these parameters vary between breeds. Isa Brown can consume over 130 g feed/day and produce eggs over 63 g (Thear, 1997), but most local breeds used in Asian countries can only produce 50-60 eggs per year per hen with a high mortality resulting from poor management and disease (Nessar, 2002). The performance of hens under different housing systems has been investigated by many researchers. Mostert et al. (1995 ) compared the performance of layers housed in a battery system (stocking density 0.1 m2/hen), a floor house system (stocking density 0.2 m2/hen) and a free-range system (stocking density 3.9 m2/hen). The free-range system had a lower egg production than both the battery and floor housing system although the egg mass of free-range and battery systems was higher than the floor housing system (60.52 and 60.98g vs 59.94g). The feed conversion (defined as kg eggs/kg feed) was better for the battery system (2.355) than both the floor house (2.535) and free-range (2.604) systems (Mostert et al., 1995). Similar results were observed by Leyendecker et al. (2001b) with white layers (Lohmann Selected Leyhorn, LSL) and brown layers (Lohmann Tradition LT), where the free-range birds had a poorer feed conversion and a higher mortality in comparison with birds in cages and

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aviaries. However, Gibson et al. (1984) reported that production from 20 to 72 weeks of age was similar for free-range birds and caged birds (283 vs 280). Feed intake was higher for free-range birds than caged birds at 36 weeks (152.4 vs 119.8 g/day/bird) and at 70 weeks (142.9 vs 123.0 g/day/bird). In this study, herbage intake of free-range birds, (estimated using an exclusion technique, Hughes and Dun, 1983), was 24-48 g dry matter/day/bird at 46, 48 and 51 weeks of age. These values are likely to be overestimated, although the birds were believed to consume considerable quantities of grass (Hughes et al., 1985). Free-range systems produce more soiled eggs than the other systems due to contamination from soil and excreta. Pavlovski et al. (1981) (cited by Mostert et al., 1995) found that there was more dirt on eggs from extensive production (8.89%) than on eggs from intensive production (1%). On farm quality control procedures in some countries prohibit the sale of dirty eggs. Dun (1992) believed that eggs from caged layers are laid into a cleaner environment and the risk of egg shells and their content becoming contaminated is much lower than in alternative systems (Mostert et al., 1995). In Australia, Glatz and Ru (2002) assessed the production of layers (Hyline Brown) in the free-range system during summer. Production was compared with the specifications published by the Hyline company for the same strain housed in cages. The free-range birds showed a higher level of mortality (mainly from culling of bullied birds) and lower rates of lay, egg weight and body weight over the period 18-40 weeks (Table 8). During the experimental period, South Australia experienced its hottest summer in a century with a maximum temperature recorded in the shelter being over 47°C. Overall, there were 17 days when the temperature exceeded 37°C in the shelter. The reduction in performance of birds relative to the cage benchmark was expected considering the heat wave conditions experienced and the reduction in the natural daylight hours after the summer solstice. However, the performance by free-range birds was similar to the data reported by Barnett (1999) on the experience with free-range egg production in Europe. Level of floor laying were less than 1% of egg production, but dirty (20%) and broken eggs were initially a problem, which was overcome by collecting eggs twice daily. Egg weight and body weight were lower than the benchmark but this was expected as birds were very active in the free-range environment. Table 8. Production performance of free-range birds compared to strain specifications over 18-40 weeks (Glatz and Ru, 2002). Treatment

Mortality and Culls (%)

Rate of Lay (%) (22 weeks)



Egg Weight (g) (40 weeks)

Body Weight (kg) (40 weeks)

Free-range 9.1 72 89 79 57.2 1.93 Standard 1.2 75 94 93 63.9 2.17 An analysis of the direct and indirect use of fossil fuel energy in three systems of egg production (battery cages, straw yards, and free-range) showed no difference in the use of energy between systems (Wathes, 1981, Table 9). Indian researchers showed that for free-range poultry, the feed cost accounted for 40.3% of total production cost, and vaccination and medication accounted for 7.1%. The overall benefit cost ratio was about 3:1 when the labour cost was not considered.

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Table 9. Edible energy outputs and efficiencies of usage of fossil fuel energy (Wathes, 1981) Battery cage Straw yard Free-range Outputs Egg (y-1) hen-housed 250 235 220 Egg mass (kg) 17.13 eggs/kg, 88% edible 12.84 12.07 11.30 Carcase live weight (kg) 2.25 2.75 3.0 Mortality (%) 8 10 12 Egg energy (MJ) 6.7MJ/kg 86.0 80.9 75.7 Carcase energy (MJ) 16.7 MJ/kg, 54% edible 18.7 22.3 23.8 Egg protein (kg P) 11.9% by weight 1.53 1.44 1.34 Carcase protein (kg P) 20.8% by weight 0.23 0.28 0.30 Efficiencies Energy out/in, E 0.165 0.163 0.147 Energy in/protein out, P(MJ/kg) 360 367 412 Quality of Free-Range Products Eggs: The specifications for a free-range egg for the British consumer include:

• a guarantee that the eggs have been produced by non-caged hens, which were allowed access to outside runs,

• an assurance that a part of the diet may have been obtained from natural organic sources, • clean and freshness, uniformity and good size, preferably brown in colour, • free from cracks, taint and unsightly inclusions, e. g. blood spots, • a firm egg shell, • air space within the egg not exceeding an appreciable volume (4mm), • non-watery, firm white (the height of the white as related to weight gives a measure called the

Haugh Units. The higher the Haugh Units the firmer the white. Fresh eggs from young hens produced eggs of 80-90 Haugh Units. Consumer resistance can be expected if Haugh Units are below 60),

• rich yellow/orange yolk and • an affordable price (Armstrong and Cermak, 1989).

While most of the eggs produced under free-range conditions can meet the above specifications, the actual value of free-range eggs is also reflected in their nutritional quality for consumers. A comparison of nutrient composition of eggs produced under different housing systems showed that the concentration of most nutrients were similar for eggs produced in battery, deep litter and free-range systems except for some vitamins (Table 10). Free-range eggs contained 50% more folic acid than battery eggs. The B12 content was 29 ug/kg for free-range eggs and only 17 ug/kg for battery eggs. The higher concentrations of vitamin B12 in the free-range may result from an increased amount of this vitamin, which was available for absorption from microbial synthesis within the birds themselves and also from litter, herbage and soil. However, no difference was found in the fat content of eggs produced under the different systems, with a mean of 109 g fat/kg egg (Tolan et al., 1974). Krieg (1963, cited by Tolan et al., 1974) reported that iron concentration were significantly higher in battery eggs (9.2 g/kg) than in deep litter (8.1 g/kg) and free-range eggs (7.6 g/kg), probably due to the ingestion of iron from parts of the cages, feed and water troughs.

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Table 10. Mean values of nutrient (per kg egg, edible weight†) in eggs under different systems of management (Tolan et al., 1974) Nutrient

No. of samples

Battery No. of samples

Deep litter

No. of samples

Free-range

Moisture (g) 68 747 49 751 32 746 Fat (g) 68 109 49 107 32 111 Nitrogen (g) 68 19.7 49 19.6 32 19.8 Protein (N×6.25) (g) 68 123 49 122 32 124 Cholesterol (mg) 68 4350 49 4480 32 4690 Ash (g) 36 9.3 25 9.1 17 9.2 Sodium (mg) 36 1390 25 1390 17 1360 Potassium (mg) 36 1350 25 1340 17 1380 Calcium (mg) 36 550 * 25 510 17 510 Iron (mg) 36 20.6 25 19.3* 17 20.8 Thiamin (mg) 35 0.91 18 0.88 12 0.90 Riboflavin (mg) 35 4.7 18 5.0 12 4.5 Nicotinic acid (mg) 35 0.68 18 0.65 12 0.70 Nicotinic acid equivalents (mg) 35 37.4 18 33.9 12 35.7 Pantothenic acid (mg) 35 17 18 18 12 18 Folic acid

(Streptococcus faecalis) (µg) 68 60* 49 100 32 90 (Lactobacillus casei) (µg) 68 250* 49 320 32 390

Vitamin B12 (µg) 68 17* 49 26* 32 29* Tocopherols (total) (mg) 68 15 49 18* 32 15 Retinol (µg) 68 1400 49 1380 32 1450 * Differences between this and other systems significant at the 1% level (p<0.01). † A 2 oz. Egg 'as purchased' has an edible weight of approximately 50g. In recent years, the lipid composition of chicken egg has been a primary area of consumer’s concern due to the relationship of specific dietary lipids with the development of coronary heart disease and some forms of cancer (Simopoulos and Salem, 1992). Lopez-Bote et al. (1998) found that eggs from poultry grazing on a natural legume grassland and herbs (supplemented with 50 g of mixed feed daily) had a higher concentration of total (n-3) fatty acids (p<0.05) and ◊-tocopherol (p<0.01) than eggs from hens fed the commercial diet. No differences in initial values or rate of oxidation were observed between treatments (Table 11). This research suggests that some constituents of grass may be of interest for the production of eggs rich in (n-3) fatty acids, without adverse oxidative effects. Coppock and Daniels (1962) reported that there were no significant differences in the fatty acid composition of the eggs produced under free-range, battery or deep litter systems.

Tolan et al. (1974) found that the amino acid composition of egg protein did not appear to be affected by the management system, but the content of some vitamins, especially for riboflavin, folic acid and B12 varied over the year. The general tendency was for these three vitamins to be greater in the second half of the year. The highest was obtained in the last quarter of the year for both riboflavin and folic acid (Table 12). This seasonal change may have been related to the age structure of the flocks and seasonal intake of these vitamins. It is more difficult to produce a consistent quality of free-range eggs across the industry because of the differences in breeds, feeds, age of birds, and management factors on different farms (Tolan et al. 1974). Smith et al. (1954) also reported that environmental temperature affects the mineral composition of eggs.

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Table 11. Fatty acid composition (g/kg total fatty acids) of the yolk fat from hens mixed feed in cages (MF) or mixed feeds and grass under free-range conditions (FR) (n=22) (Lopez-Bote et al., 1998) Fatty acids MF FR SEM P>Fa C14:0 0.32 0.39 0.006 0.003 C14:1 0.04 0.06 0.004 NS C15:0 0.09 0.10 0.012 NS C16:0 24.04 27.00 0.225 0.001 C16:1(n-9) 0.70 0.26 0.042 0.002 C16:1(n-7) 2.27 2.65 0.085 NS C18:0 13.11 14.05 0.692 NS C18:1(n-9) 35.98 36.91 0.794 NS C18:1(n-7) 0.08 0.10 0.003 0.071 C18:1(n-6) 18.70 12.00 0.488 0.001 C19:0 0.11 0.11 0.003 NS C18:3(n-3) 0.39 0.99 0.070 0.065 C20:0 0.02 0.04 0.001 0.001 C20:1(n-9) 0.25 0.26 0.006 NS C20:3(n-9) 0.19 0.22 0.022 NS C20:4(n-6) 2.11 2.01 0.041 NS C20:5(n-3) 0.02 0.15 0.021 0.044 C22:1(n-9) 0.01 0.11 0.029 NS C23:0 0.02 0.01 0.005 NS C22:4(n-6) 0.19 0.28 0.005 0.001 C22:5(n-6) 0.58 0.43 0.024 0.028 C22:5(n-3) 0.13 0.31 0.029 0.032 C22:6(n-3) 0.62 1.57 0.063 0.001 ∑ (n-3) 1.16 3.02 0.162 0.001 ∑ (n-6) 21.59 14.72 0.491 0.001 ∑ (n-6)/∑ (n-3) 18.73 5.21 0.449 0.001 ∑ sat 37.71 41.68 0.763 0.072 ∑ mono 39.34 40.35 0.836 NS UIb 95.08 91.01 1.497 NS SEM: standard error of means Table 12. Quarterly mean values (per kg egg, edible weight) for nutrients which showed a significant seasonal pattern in UK (Tolan et al., 1974) Nutrient Jan-Mar* Apr-Jun Jul-Sept Oct-Dec Roboflavin (mg) 4.3 4.7 4.7 5.5 Folic acid (ug) 300 250 300 400 Vitamin B12 23 23 27 23 * Means of 1967 and 1968 It should be expected that the interaction in egg quality between poultry strain and housing system can occur in practice. For example, Leyendecker et al. (2001b) examined egg quality of white layers (Lohmann Selected Leghorn, LSL) and brown layers (Lohmann Tradition, LT) in battery cages, aviary and free-range systems and revealed no consistent advantage for any housing systems. Both layer lines exhibited higher Haugh Units in the aviary. The highest yolk colour was found in the free-range system for LSL-hens and in battery cages for LT-hens. The number of meat spots was significantly lower in eggs of the LT-hens kept in the free-range system. Shell thickness: Shell thickness is one of the major egg quality parameters and is influenced by a number of factors including housing system. Early research demonstrated that shell thickness was greatest on free-range, intermediate on deep litter and least in battery cages (De Jong, 1963, Pavlovski et al., 1981 cited by Mostert et al., 1995). This finding has been further confirmed by Mostert et al. (1995), who reported that shell thickness of eggs produced in the free-range system was 1 um and 0.94 um thicker than that of eggs produced in the battery and floor house systems, respectively. Hughes et al. (1985) found that shell strength was slightly greater in eggs from hens on range. These free-range

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eggs required significantly more energy to crack, both at 36 and at 70 weeks. Shell deformation was less in eggs from the range, but the differences were small. Meat: The appearance and colour of meat is a primary quality trait considered by consumers when making purchase choices. It has been realised that there is considerable variation in colour of breast fillets of commercial broilers. However, there is little information on the colour of free-range chicken meat. It is expected that a seasonal change in meat colour should occur given that seasonal changes in feed supply for free-range poultry. This seasonal effect was clearly demonstrated in turkey, where lightness values were lowest in winter and highest in summer, although the magnitude of these differences was small (McCurdy et al., 1996 cited by Barbut, 1998). However, Wilkins et al., (2000) found no seasonal effect on colour of breast although two free-range flocks produced breast fillets slightly, but significantly lighter and less red compared with intensive housed birds. Dunn et al. (1993) compared the texture of chicken meat produced by free-range poultry and poultry housed in cages. The outcomes of this study showed no significant difference in mean ultimate pH values of the breast muscle of the free-range and standard broilers. Free-range meat tended to be low in pH with 46% of these birds having pH below 5.6. In comparison, only 25% of standard broilers had pH values below 5.6. Free-range and standard broiler muscle had similar mean sarcomere lengths, cooking loss and shear force. However, the comparison in this study may not be valid because free-range birds were all female with an average age of 60 days whereas the standard broiler birds were predominantly male with an age of 45 days. The sex and age effect on texture of chicken meat could not be differentiated from the housing effect. Residues in free-range eggs: Free-range poultry are able to express their foraging behaviour, but can also have access to the herbicide and insecticide applied to pastures and/or crops. Consumers are becoming more concerned about residues of these products in free-range eggs. Early study by Holmes et al. (1969) showed that the compounds most frequently detected in the eggs were gamma-BHC, pp’-DDT and pp’-DDE, which is the first toxic metabolite or breakdown product of DDT. The free-range eggs had much higher DDT compounds (Table 13). Nevertheless, nearly 60% of these eggs contained residues which did not exceed 0.05 ppm. Only 3 samples contained 0.12-0.40 ppm gamma BHC, and 8 samples contained 0.15-3.8 ppm pp’-DDT. This suggests the management of free-range birds is a key to avoiding eggs being contaminated with insecticides. Table 13. Pesticide residues (ppm) in eggs from agricultural institute farms without thermal vaporisers (Holmes et al., 1969) System Samples a-BHC pp’-DDE pp’-DDT Battery 86 Mean 0.02 0.02 0.03 Range 0-0.30 0-0.20 0-0.37 Deep-litter 54 Mean 0.04 0.02 0.04 Range 0-0.33 0-0.13 0-0.31 Free-range 33 Mean 0.04 0.36 0.54 Range 0-0.40 0.01-2.8 0-3.8 Welfare and Behaviour of Free-Range Poultry As discussed in previous sections, free-range systems are more suited for birds to express their behavioural requirements with main feature being freedom of movement, choice of nesting site, type of flooring, space to escape or chase other birds during a social encounter and choice of neighbour (Armstrong and Cermak, 1989). However, it is difficult to judge the housing conditions at farm level from an animal welfare point of view due to many variable factors on farms. An animal needs index was developed by Bartussek in 1985 and updated many times since (Bartussek 1999). One principle of the index system is the possibility of compensation because unfavourable conditions in one area may be balanced to a certain extent by better conditions in another area. Horning et al. (2001) assessed the housing conditions of 63 hen houses using this index system. He found that deep litter

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system achieved fewest points, followed by aviaries and free-range systems. Farms with both covered runs and free-range scored most points (Horning et al., 2001). Within this scoring system, high scores were given for optimum density, ability of birds to access feed, water, perches, nests, outdoor runs, litter scratching areas and plumage condition. However, in this scoring system it was surprising that little importance was given to bird health and air quality. Pecking: Feather pecking in laying hens is a serious animal welfare problem in poultry housing, as it may lead to feather damage, injuries and mortality (Hughes and Duncan, 1972, Allen and Perry, 1975). Recent studies show a positive correlation between feather pecking and egg production (Kjaer et al., 2001), indicating that a continuous selection for higher productivity results in birds having an increasing tendency to perform feather pecking unless precaution is taken to reduce it (Kjaer and Sorensen, 2002). Apart from breeding and selection, nutritional factors also contribute to the feather pecking. If hens are offered feed that does not meet their requirement of one or more specific nutrients, the level of feather pecking and cannibalism will be increased (Siren, 1963, Neal, 1956, Ambrosen and Petersen, 1997). However, Kjaer and Sorensen (2002) suggested that the dietary level of methionine + cystine, light intensity during rearing and age at access to the range area, had minor effects on the pecking behaviour. Higher levels of fear have been associated with higher levels of feather pecking (Blokhuis and Beutler, 1992). Feather pecking should be regarded as redirected foraging behaviour (Huber-Eicher and Wechsler, 1997) and can be reduced if layer birds are provided with incentives that elicit foraging behaviour, such as litter (Hughes and Duncan, 1972, Simonsen et al., 1980, Blokhuis and Arkes, 1984, Blokhuis, 1986), longcut straw from perforated plastic baskets (Norgaard-Nielsen et al., 1993) or polystyrene blocks (Huber-Eicher and Wechsler, 1997, Wechsler and Huber-Eicher, 1998). Despite the provision of straw materials, feed form also has a significant effect on the feather pecking (Aerni et al., 2000, Table 14). Chicks that could use both sand and straw from day 1 on did not show high rates of feather pecking, and no injuries were observed in these groups. On the other hand, foraging activity was inversely related to the rate of feather pecking, and the occurrence of feather pecking could be delayed from week 4-7 weeks by postponing procedures that led to changes in foraging behaviour. Based on these research outcomes, free-range system that promotes foraging behaviour is effective in reducing and preventing feather pecking (Huber-Eicher and Wechsler, 1997). Housing conditions and suitable pastures for free-range production that promote foraging behaviour, such as the provision of litter or floor grain, are effective in reducing feather pecking, although there is a risk of pathological feather pecking occurring when straw or wood shavings are used as litter. Also, in barn and free-range systems, birds that are dustbathing flick litter or dust onto their backs and this can attract the attention of other birds resulting in pecking of the particles. This can lead to pecking around the base of the tail (near the preen gland) and may result in the development of cannibalism. Table 14. Effects of foraging material and food form on the percentages of hens engaged in different activities in scan samples. Means as well as minimum and maximum values (in parentheses) of 4 pens per housing condition, P values derived from ANOVA (Aerni, et. al., 2000) Behaviour Housing conditions P values Pellets/Straw Mash/Straw Pellets/No

straw Mash/No

straw Foraging material

Feed form

Interaction

Foraging 31.3 (23.3, 37.8)

22.4 (15.3, 28.8)

10.3 (8.7,12.1)

8.8 (6.5, 10.6)

<0.0001 <0.05 NS

Feeding 17.1 (15.6, 20.7)

29.3 (25.3, 32.4)

18.2 (16.1,21.3)

32.3 (28.3, 35.4)

NS <0.0001

NS

Preening 2.1 (1.6, 3.5)

1.7 (1.4, 1.9)

4.8 (2.6, 6.6)

2.8 (1.9, 3.1)

<0.0002 <0.05 NS

Dustbathing 2.1 (1.0, 3.9)

3.1 (1.8, 5.7)

0.2 (0, 0.6)

0.3 (0, 0.6)

<0.0001 NS NS

Moving 2.0 (1.5, 3.2)

1.6 (1.3, 2.0)

4.7 (2.4, 6.8)

2.7 (1.8, 3.1)

<0.002 <0.05 NS

Perching 16.4 (8.3, 27.4)

13.3 (6.1, 22.8)

34.2 (26.1, 40.3)

19.7 (19.1, 20.5)

<0.005 <0.03 NS

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Layout of house and free-range: To solve the problems of feather pecking and cannibalism the layout of the house and the free-range is being examined. In particular changing the position of nests, perches and feeders in the house have shown some potential. Flocks that use the outside area well showed less tendency to feather peck (Fiks van-Niekerk, 2001). Hofner and Folsch (2001) reported a trial where small trees provided hens a shelter belt and variety of food including fruits and small leaves. The cover in the outside area resulted in hens spending more time outside. In trials with 10 breeds more cannibalism was recorded in the nest boxes with sloping floors compared to groups with flat littered nests. Presumably cannibalism was initiated due to the more restless behaviour of hens using sloping nests (Keppler et al., 2001b). Group size: Work continues in Europe examining optimum group size for free-range hens. Birds utilising the outdoor area decreases as the group size increases (Keeling et al., 1988).

Genetic: An enormous research effort is being directed toward improving the rate of genetic progress by developing a simple quick test, which predicts a bird’s likelihood of developing feather pecking. This will eliminate the need to observe feather pecking of the hen throughout the laying cycle. Studies indicate the degree of avoidance of a novel object (brown ceramic bowl, loose bundle of straw and loose bundle of feathers) was not predictive of the tendency to peck in ISA Brown hens (Albentso and Nicol, 2001). There is evidence of an additive genetic effect underlying feather pecking behaviour with heritability ranging from 0.1-0.4. For cannibalism there is an indication of one or more major genes having influence. The likely candidate is the glucocorticoid receptor gene. Selection lines differing in the propensity to feather peck or engage in cannibalistic pecking have been developed with a heritability of around 0.2-0.7 respectively (Kjaer, 2001). Molecular studies are aiming to identify genes that cause differences in feather pecking (Korte et al., 1997). Breed: Breed has an influence on feather pecking and cannibalism in laying hens. Five breeds of brown egg laying hens exhibited differences in intensity of feather pecking and the occurrence of skin injuries in the laying period (Keppler et al., 2001a) suggesting use of birds in alternative systems can be successful provided the disposition of the breed to feather pecking and cannibalism is low. Vocalisation: High feather pecking lines vocalise more than low feather pecking lines offering a measure for detecting the potential of feather pecking (Koene et al., 2001). Behaviour studies: Behaviours related to traits such as fear, sociality, coping style are being measured together with observations on feather pecks and pulls and by electronic recording of strong pecks and pulls. The results suggest that feather pecking and cannibalism is not closely related to behavioural characteristics (Hocking et al., 2001). In contrast Savory and Mann (1997) showed performance of certain behaviours (feeding, preening) may attract feather pecking and that feather peckers tend to be more active. Hens direct ground pecking behaviour to feathers of pen mates when they are deprived of access to litter or forage (Kim-Madslien and Nicol, 1998). Increased stress associated with frustration may be responsible for the initial difference in pecking rates, although it appears to be more stimulated by increased ground pecking motivation (Kim-Madslien and Nicol, 2001). Familiar odours: Olfactory memory exists in domestic chicks and could be used as reassuring agents when poultry are exposed to otherwise unfamiliar and frightening situations. For example imprinted odorants might serve to reduce the reluctance for poultry to venture into an unfamiliar and exposed area like a free-range (Jones et al., 2001). Husbandry: The sides of a brooder covered with feathers (0.5 lux) versus open sided brooders (5-6 lux) with and without food deprivation were tested to determine the number of feather pecks (severe

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and gentle) in Lohmann untrimmed chicks (Johnsen and Kristensen, 2001). No differences were found in plumage condition of birds at 30 days of age and rearing with a dark brooder did not prevent development of feather pecking. Food deprivation increased the level of severe feather pecking and reduced dustbathing although it is unclear whether this is a result of misdirected ground pecking or redirected dustbathing pecks. Feed structure: Fine feed encourages hens to feed longer than coarse feed decreasing the incidence of feather pecking and resulting in better plumage cover (Walser and Pfirter, 2001). Fine feed had a low percentage (0-13%) of feed particles with a diameter greater than 2 mm compared to the coarse feed (33-55%). An optimal feed structure consists of particles between 0.25-2 mm for birds in alternative systems. Nutrition: Early studies in Switzerland indicated that increased levels of dietary fibre and magnesium content may reduce the incidence of feather pecking and cannibalism. However more recent work suggests that increasing Mg content from 0.135% to 0.27% and fibre from 2.5% to 4% had no major effect in lowering the incidence of cannibalism in brown laying hens (Hadoorn et al., 2001). In contrast Choct et al., (2002) reported a reduction in cannibalism in birds fed diets with higher levels of fibre. Hadoorn et al., (2001) suggest that low dietary levels of methionine and linolenic acid may be more important in increasing feather pecking and cannibalism. Whole wheat feeding of Lohman leghorn and brown hybrid from 8-16 weeks had no influence on plumage condition or mortality rate (Hadoorn and Wiedmer, 2001). Foraging behaviour: Very limited data is available on the foraging behaviour of free-range poultry. A study conducted in a dry summer in South Australia showed that birds were very active in the paddock during overcast conditions and also when light drizzly rain was falling. It was apparent that birds were attracted to the insects which were more active during this period. Birds foraged mainly within 30-40 m of the shelter but would also forage further out into the paddock especially when attendants were present. As the birds moved further out into the paddock they tended to leave clumps of pasture. Keppler and Folsch (2000) directly observed the locomotive activity of hens and cocks in aviary systems with and without free-range. The hens in the aviaries without free-range moved between 340 m and 634 m per day. The cocks moved larger distances when foraging (795 m - 1445 m). The hens moved longer distances in connection with food-intake (13 - 31 %) than the cocks (1.3 - 13.7 %). The hens in the aviary with free-range moved distances of 1800 m and 2500 m per day. This study showed that hens and cocks show an extensive locomotive behaviour under free-range conditions. Further research on foraging behaviour of free-range poultry is required as the outcomes of this type of research will assist free-range producers to develop management strategies to improve foraging ability of poultry. Temperature: In modern housing under intensive conditions, the birds are housed in a temperature-controlled shed. This prevents stress caused by low or high temperatures and enables the bird to achieve maximum production. However, under free-range conditions, birds are exposed to extremely high or low temperatures, which not only influences the performance of birds but also the welfare. The use of water spray to cool birds is one of the strategies to reduce the impact of high temperature on foraging birds. In winter, free-range poultry might need more protection from cold weather, which might not be so crucial in Australia where the winters are not as cold as those in Europe and some Asian Countries. Ward et al. (2001) found no difference in resistance to heat loss attributable to rearing environment for plumage from the back and leg, but a significant difference in the pectoral region. Free-range birds had a thicker plumage and a higher total resistance to heat transfer in the pectoral region, despite showing a lower resistance per unit depth than broiler birds. Free-range birds can behaviourally thermoregulate by remaining inside the hen house to reduce heat losses.

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Predators: It is recognised that free-range birds are under the risk of predation from foxes, wild cats, eagles and hawks. It is not clear whether this should be a welfare issue for free-range poultry because birds are subject to a similar risk under natural conditions. In UK, some farmers allow birds to have access to paddocks during all of the daylight hours and in some instances this involves a farmer being present late in the evening to shut the pop-holes. One farm in the UK shut the pop-holes at the end of the working day, but left a single pop-hole open. This pop-hole had bars about 10-12 cm apart to exclude foxes. This apparently worked well unless there was an identified fox problem, in which case control programmes were required (Barnett, 1999). While the establishment of proper fence may prevent birds from fox and cat attacks, the owl, eagle and hawk are difficult to control. Bone development: Currently leg weakness in layers is a welfare concern in cage production system. High energy and protein levels in the diet to maximise production and lack of physical exercise contribute to the problem. Free-range offers the freedom for poultry to exercise in the paddock, which might reduce leg weakness problems and improve the development of bone. Gregory et al. (1990) found a higher incidence of broken bones in birds in battery cages compared to free-range and perchery systems. It was revealed that battery birds had a higher incidence of recently broken bones than perchery and free-range birds. However, the perchery and free-range birds had more old breaks than battery birds. The pain and discomfort associated with the old breaks was borne over a longer period than the breaks which occurred during depopulation of birds from the battery system. Leyendecker et al. (2001a) also reported that the bone breaking strength was consistently higher for hens kept in the aviary or in free-range system compared to battery cages. Pathology and histology studies proved that free-range hens, and deep litter hens suffered from pododermatitis, keel bone deformation and amputated beaks in addition to pecking wounds. In caged hens, however, severe fatty liver syndromes, injuries of the claws and inflammation of the feather follicles were mainly found (Keutgen et al., 1999). Conclusion and Future Development Free-range growers need to have a good knowledge of stockmanship and animal health management, as the birds being used at the present time are not hardy enough for climatic extremes and lack the immunity to the wild strains of common diseases. With a strong demand by consumers for free-range egg products, there is a need to develop new strains that will handle harsh environmental conditions with a reasonable production capability. Asian researchers have already started to crossbreed their local strains with commercial ones. The outcomes of these breeding programs will have a significant impact on free-range production. European poultry breeding companies are also developing birds more suited to free-range. Within these breeding programs, metabolic stability, strong plumage and docile behaviour continue to be selection priorities.

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Review of Production, Husbandry and Sustainability of Free-Range Pig Production Systems

Abstract A review was undertaken to obtain information on the sustainability of pig free-range production systems including the management, performance and health of pigs in the system. Modern outdoor rearing systems requires simple portable and flexible housing with low cost fencing. Local pig breeds are generally more suitable for free-range systems. Free-range farms should be located in a low rainfall area and paddocks should be relatively flat, with light topsoil overlying free-draining subsoil with the absence of sharp stones that can cause foot damage. Huts or shelters are crucial for preventing pigs from direct sun burn and heat stress, especially when shade from trees and other facilities is not available. Pigs commonly graze on strip pastures and rotated between paddocks. The zones of thermal comfort for sows (12-22oC) and piglets (30-37oC) differ markedly. Offering wallows to free-range pigs meets their behaviour requirements, and also overcomes the effect of high ambient temperatures on feed intake. Pigs can increase the evaporative heat loss via an increase in the proportion of wet skin by using a wallow, or through water drips and spray. Mud from wallows can also coat the skin of pigs, preventing sunburn. Under grazing conditions, it is difficult to control the fibre intake of pigs although a high energy, low fibre diet can be used. In some countries outdoor sows are fitted with nose rings to prevent them from uprooting the grass. This reduces the risk of infection in pigs and nutrient leaching of the land. Free-range pigs have a higher mortality compared to intensively housed pigs. Many factors can contribute to the death of the piglet including crushing, disease, heat stress and poor nutrition. With successful management, free-range pigs can grow as fast as indoor pigs, although the growth rate of the litters is affected by season. Piglets grow quicker indoors during the cold season compared to outdoor systems. Pigs reared outdoors have shown calmer behaviour. Aggressive interactions during feeding are lower compared to indoor pigs while outdoor sows are more active than indoor sows. Outdoor pigs have a higher parasite burden, which increases the nutrient requirement for maintenance and reduces their feed utilization efficiency. Parasite infections in free-range pigs also risk the image of free-range pork as a clean and safe product. Diseases can be controlled to a certain degree by grazing management. Frequent rotation is required although most farmers are keeping their pigs for a longer period before rotating. The concept of using pasture species to minimise nematode infections in grazing pigs looks promising. Plants that can be grown locally and used as part of the normal feeding regime are most likely to be acceptable to farmers, particularly organic farmers. However, one of the key concerns from public for free-range pig production system is the impact on the environment. In the past, the pigs were held in the same paddock at a high stocking rate, which resulted in damage to the vegetation, nutrient loading in the soil, nitrate leaching and gas emission. To avoid this, outdoor pigs should be integrated in the cropping pasture system, the stock should be mobile and stocking rate related to the amount of feed given to the animals. Keywords: Free-Range Pig, Sustainability, Production, Management, Husbandry. Introduction Recently there has been commercial interest in the pork products originating from natural animal production systems because consumers have become more interested in buying products from animal that are kept in welfare friendly systems. Intensive pig farming is considered to compromise the welfare of the pigs and there is a perception that there is widespread use of synthetic chemicals (e. g. medication and growth promoters) in the feed (Barton-Gade, 2002). The widespread concern for animal welfare, the high capital cost of intensive pig production and the increasing demand for organic pork has put pressure on the pig industry to develop systems which enable the pigs to behave naturally (Petersen et al., 1995; De Jonge et al., 1996). As a result there has been an increasing search for simpler, less capital-intensive systems for the production of pork under ecologically, sustainable non-intensive conditions.

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Free-range pig production systems has been included as one of the main targets for the European and North American pork industries (Sather et al., 1997). It is believed that pigs under this system can express their natural behaviour and have reduced stereotypic behaviour. Free-range pork has superior taste compared to pork produced in intensive condition and has health benefits for humans due to the increased total n-3 and n-6 polyunsaturated fatty acids (PUFA) of neutral lipids and total n-3 of polar lipids (Muriel et al., 2002; Simopoulos, 1991). These polyunsaturated fatty acids are essential for growth and development in humans (Simopoulos, 1991). With these advantages, the number of pigs kept outdoors has increased dramatically in the last 20 years. For example, 25% of the breeding sows are kept outdoors in the UK (Sheppard, 1998). The number of free-range pig farms in France increased from 209 in 1984 to 1608 in 1994. In Australia there is an increasing trend to keep sows outdoor and to grow pigs in straw-based shelters (Henschke, 1999). The use of low cost eco-shelters and electric fencing has resulted in an increase in outdoor pig production (Dagorn et al., 1996) and reduced behavioural disturbances, especially during parturition in sows (Andresen and Redbo, 1999). However, a successful free-range production system requires producers to have suitable pig breeds and sound knowledge of management. As a result, the purpose of this review is to describe the free-range production systems currently been used including the breeds, pig management, performance, disease problems and sustainability of free-range systems. Description of Production Systems From an animal welfare point of view, the free-range system is the preferred option. The system of outdoor rearing was traditionally thought to involve high labour, low cost, and low management. Modern outdoor rearing system requires simple, portable housing, watering systems and feeders. Pigs and huts are moved with a tractor, loader, hydraulic cart, or all-terrain vehicle. Low cost, portable electric fencing works well. Structures are dispersed over several acres, and animals distribute manure naturally. Straw and corn stalks can serve as bedding. However, there are different systems for pigs at different physiological stages. Growers: The growers are housed in semi-intensive conditions in large covered yards or pens with straw bedding. The piglets are kept outdoors for less than four weeks. Approximately 50% of outdoor bred piglets are transferred to intensive units for finishing. Growers are finished (slaughtered) at about 22 weeks, when they reach weight about 95 kg (Baker, 2002). Breeders: Once the gilts have been artificially inseminated (AI) in indoor pens, they are moved to outdoors in small groups in mobile arcs with access to mud wallows, essential in the summer to help the sows keep cool. A week before farrowing they are transferred to individual outdoor grassy paddocks with insulated arcs with abundant straw bedding. The whole operation falls within the farm's rotational system. Piglets are weaned at 24 days at which point the sows go back into the shed and the cycle starts again. The sows are re-served, stay indoors for four weeks before going back into the fields. Pasture farrowers typically stock 7 to 15 sows and litters per acre. When a sow has 6 to 8 litters, at around four to five years old, it is sold and slaughtered (Baker, 2002). In Europe, the system involves outdoor fenced paddocks holding groups of sows. At around 15-25 sows per hectare, the stocking density is equivalent to a minimum of 40 sows, a very much lower density than the 1.5 m2 per sow in a stall. Accommodation for pregnant sows is made from corrugated-iron 'arcs', each housing 5-6 sows. In this system, the sows forage and root in the grassy enclosure at will (Metcalfe, 2001). Suckling pigs: The piglets are kept outdoor for less than four weeks before they are weaned and transported to a 'nursery' unit and/or 'finishing' unit (Baker, 2002).

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Breeds for Free-Range Pig Production The ideal breeds for a free-range pig system should perform well under a very harsh environment, exhibit resistance to disease and have high feed conversion efficiency, especially for fibrous materials. These criteria make it necessary to breed new pig genotypes more resistant than those currently available for free-range system, especially because growth-stimulating hormones and antibiotics are banned. The University of Agricultural Science (Godollo, Hungary) developed a new crossbred variety (Hungarian Large White, 75%) x Mangalica (pig with curly bristles, 25%) for these purposes (Hungamang Standard, 1990 cited by Dworschak et al., 1995). Ru and Glatz (2001) also demonstrated that a cross breed of the two commercial pig breeds (Landrace x Large White), could be used for free-range production under southern Australian conditions. One approach is to cross the current commercial breeds with local breeds which are often resistant to diseases and the harsh environment. McGlone and Hicks (2000) assessed two crossbred genotypes containing 15% Camborough and 25% Meishan, respectively under outdoor conditions. They found that the 25% Meishan had greater reproductive performance and weaned 1.7 more pigs per sow than the Camborough-15. Local pig breeds are often more suitable for free-range systems and are widely available. A typical example is the Iberian pig which is produced in free-range conditions in evergreen-oak forest located in the South West of Europe. The natural diet consists mostly of acorns and grass. The high quality pork obtained from the Iberian pigs is attributed mainly to this feeding regime (Lopez Bote and Rey, 2001). Mayoral et al. (1999) also reported that the Iberian pig is the only free-range pig breed of importance in the Spanish meat market, with nearly two million animals slaughtered per year (Lopez-Bote, 1998). Profitable Iberian pig production is based on the gourmet quality of the dry-cured meat products (Antequera at al., 1992; Ruiz et al., 1998). Managing Free-Range Pigs Housing: The selection of a site for housing free-range pigs requires consideration of the welfare of pigs and the impact on the environment and the local community. Sites exposed to wet and windy conditions greatly increases the potential for poor welfare in outdoor systems (Thornton, 1990; Anon., 1996). Recommendations from the UK indicate that farms should be located in a low rainfall area and paddocks should be relatively flat, with a light topsoil overlying a free-draining subsoil with the absence of sharp stones that can cause foot damage (Thornton, 1990). In Australia, it is recommended that outdoor production should be confined to regions where temperature rarely exceeds 30°C, a low rainfall, gently sloping land to reduce the risks of flooding and movement of straw, and a variety of soil types (Barnett et al., 2001). However, these recommendations can be changed if a proper management system is in place. A typical example is for free-range pigs which performed very well in a hot dry summer in South Australia (>35oC) where wallows and a fogger system was supplied. After two years study on the physical and chemical impact on the soil from outdoor pig production on different Swiss farms, Zihlmann et al. (1997) gave the following recommendations for an environmentally-friendly outdoor pig production; 1) heavy soil, low rainfall and good grass cover, 2) an area of at least 0.015-0.02 ha per fattening pig and 0.03-0.05 ha per sow for a rotation area of four-months in the plot, 3) the location of the huts should be changed from time to time, 4) feeding places should be provided with a hard surface, and 5) the copper and zinc content of the feed should not exceed animal requirements. House design should be flexible, depending on the environment conditions. In Australia, cheap mobile eco-shelters have become very popular for outdoor pigs. Some farmers are using straw huts which reduce the housing and bedding cost for grazing pigs although the performance under this system has not been assessed. It is clear that hut design for outdoor pigs can affect pig production. McGlone and Hicks (2000) found that litters farrowing in the English-style huts weaned 1.5 more (P<0.05) piglets per sow than did litters in the American-style huts. English huts with four straight-sided walls were bigger than American huts (4.28 vs 3.32 m2) and bedded with wheat straw.

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Stocking rate: A survey conducted in UK for a total of 30,423 breeding sows showed that average stocking rates in sow, dry sow and farrowing paddocks were 13.4, 10.9 and 7.8 pigs/acre respectively and average hut lying areas (m2/pig) were 1.2, 1.6 and 3.9. The average pre-weaning mortality was 12.1% for all hut types and a crushing was involved in 98% of piglet death. Average weaning age and weight were 24.5 days and 7.1 kg, respectively (Abbott et al., 1996). Water and feed allowance: While water should always be available for free-range pigs, the feed allowance is variable, depending on the quantity and quality of forage in the paddock available for the pigs. Pigs commonly graze on strip pastures and rotated between paddocks. Also outdoor pigs can be fed ad libitum on a conventional growth feed until the animals reach a weight of 60 kg and thereafter provided a restricted diet of 2.8 kg per pig per day (Hogberg et al., 2001). Heat release: Free-range pigs are exposed to the impact of a number of environmental factors. Among these, temperature is one of the key factors determining the success of free-range production systems. When the temperature is below the lower critical temperature (LCT), pigs must increase heat production through shivering and other metabolic processes to maintain body temperature. On the other hand, when the temperature is higher than its evaporative critical temperature (ECT), the evaporative heat loss of pigs begins to increase, particularly from the lungs, through increased respiration. The zones of thermal comfort (temperature between LCT and ECT) for the lactating sow and piglet differ markedly, between 12-22oC for the sow and 30-37oC for piglets (Black et al., 1993). Capstick and Wood (1922) and Heitman and Hughes (1949) reported that the critical temperature for optimum performance of pigs weighing more than 75.34 kg is between 15.5 and 21.1oC. Pigs are not able to sweat and are more sensitive to hot than cold conditions (Ingram, 1965). Most researches have focused on the effect of high temperature and have clearly demonstrated that ambient temperatures above the ECT of lactating sows leads to a reduction in food intake, milk yield, reproductive performance and growth rate of piglets. Black et al. (1993), reviewed a number of studies and found that for each 1oC increase in ambient temperature above 16oC, daily voluntary energy and food intake of lactating sows decreased by 2.4 MJ DE and 0.17 kg, respectively. However, the relationship between ambient temperature and food intake is unlikely to be linear over the range of temperature and the decrease in intake may depend on the extent to which ambient temperature exceeds the animal’s ECT (Giles and Black, 1991). Mullan et al. (1992) also reported that feed intake was depressed by approximately 25% and milk yield by 15% for sows housed at 30oC compared with those housed at 20oC and the high ambient temperature had a direct effect on milk yield. The reduction in food intake of the lactating sows and growing pigs is associated with an increase in deep body temperature. The direct effect of high temperatures on milk yield may result from a redirection of blood flow to skin and away from other tissues, including the mammary gland. Oxygen uptake of lactating sows decreased from 523 to 411 ml/min when ambient temperature was increased from 18 to 28oC. This decline of 20% in heat production was associated with a 25% decline in milk yield and 40% reduction in food intake (Black et al., 1993). The effect of high ambient temperatures on voluntary food intake also has important consequences for reproductive performance. Primiparous sows lactating during summer have a greater interval between weaning and mating than do those during winter, but season does not appear to have the same effect with multiparous sows (Clark et al., 1986), probably because the young animal mobilises a greater proportion of its more limited body reserves if voluntary feed intake is low during lactation. There is conflicting evidence on the mechanism by which the season influences reproductive performance. Evidence from primiparous sows suggests that the high ambient temperatures during lactation causes a decrease in luteinizing hormone (LH) pulse frequency and that this is responsible for the delay in rebreeding after weaning (Barb et al., 1991). However, there is also evidence that low nutrient intakes in primiparous sows, housed under standard conditions during lactation cause an increase in the weaning to mating interval and this is due partially to a disruption of the normal secretory pattern of LH (Mullan et al., 1991). Feed intake (Barb et al., 1991) was reduced from 6.1 to 2.9 kg/day due to the effect of high ambient temperatures.

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The reduction in growth rate of piglets that are suckling sows maintained at high temperatures has been assumed to reflect a reduction in milk yield. For example, Schoenherr et al. (1989b) and Vidal et al. (1991) recorded decreases in milk yield of 10 and 35% and an associated decline in piglet growth rate when ambient temperature was increased by 8oC and 10oC, respectively. Milk yield of sows exposed to high temperatures can be improved by reducing normal heat production or increasing heat loss to the environment. Pigs can adjust their behaviour to adapt to the harsh environment. For example, on hot days, pigs cool themselves by using a wallow or going under water sprinklers (Heitman et al., 1962), or seek protection from the sun in the shade (Heitman et al., 1962; Blackshaw and Blackshaw, 1994) when such facilities are available. Pigs can also increase their heat loss by moving away from hot places to a cooler floor or a place with higher air velocity, changing their lying posture from belly to side, or by avoiding body contact with other pigs (Geers et al., 1986). On hot days pigs attempt to lie in a damp place or wallow, or even bathe in a standing position, as they do in natural conditions (van Putten, 1978). By rolling from side to side in the wallow or damp place (van Putten, 1978), the moist upper side of their bodies will be cooled by evaporative heat loss (Ingram, 1965). However, wallowing is not only performed on hot days but also on cooler days, suggesting that wallowing also plays a role in skin and hair care (van Putten, 1978). Free-range pigs are exposed to variable environmental conditions where the temperature fluctuates seasonally and daily resulting in variable feed intake, milk yield and growth rate of pigs. Based on these facts, a number of strategies have been examined to reduce heat production and/or increasing heat loss, including offering cooling systems and feeding appropriate diets. Wallow: Offering wallows for free-range pigs will not only meet their behavioural requirements, but also overcome the effect of high ambient temperatures on feed intake. Pigs can increase the evaporative heat loss via an increase in the proportion of wet skin. Mud from wallows can also coat the skin of pigs, preventing sunburn. Black et al. (1993) used an Auspig model to predict the effect of wet skin on feed intake of sows and found that an increase in the proportion of wet skin improved feed intake and shortened weaning to mating interval of sows (Table 15). Table 15. Ambient temperature in relation to evaporative critical temperature (ECT) for the sow and its effect on the predicted1 performance of a sow and litter during a 28-day lactation (post-partum body weight of 150 kg, fed a diet containing 13.5 MJ DE and 164 g crude protein per kg dry matter, litter size of 9, no creep feed provided) (Black et al. 1993) Treatment Thermal comfort (dry) Proportion of wet skin Sow2 Piglet3 15-304 1005 Temperature (oC) Ambient 20 33 33 33 ECT 22 26 25 21 Sow Feed intake6 (kg/day) 5.26 2.61 4.31 5.26 Digestible energy (DE) Intake (MJ/day) 71 35 58 71 Weight change (kg) +1.8 -29.1 -9.6 +1.4 Weaning to mating interval (days) 5.0 19.1 9.6 5.0 Latent heat loss of evaporation from skin (MJ/day)

10.9 10.5 16.0 25.9

Piglet Average daily gain (g) 152 168 193 194 Mean weight at weaning (kg) 5.64 6.08 6.79 6.80 1Predicted by Auspig model (Black et al., 1986) 2Zone of thermal comfort for sows 3Zone of thermal comfort for piglets 4Simulating the effect of drip cooling by increasing the proportion of wet skin for the sows from 15 to 30% 5Simulating the situation where the proportion of wet skin for the sow is up to 100% 6Does not include feed wastage.

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Using a wallow to improve outdoor pig performance is not new. Early research showed that the rise in respiration rate and rectal temperature was reduced in swine with access to the wallow. At temperatures over 26.7oC, the use of a wallow increased appetite, rate of gain, and efficiency of feed utilisation (Jackson, 1938; Culver et al., 1960). Pigs being fattened on pasture in Louisiana with the use of a wallow, increased daily gain nearly 181.6 g per pig during a 73-day period (Bray and Singletary, 1948). However, pigs use the wallow for lying and oral behaviour within the temperature range (-4 to 24oC), but the duration of these behavioural patterns increased when the temperature exceeded 15oC (Olsen et al., 2001). However, the effectiveness of wallow in a southern Australian summer is questionable when the temperature is over 38oC. Under this environment, the establishment of wallow in the shaded area may be beneficial (Ru and Glatz, 2001). An early study by Garrett et al. (1960) clearly demonstrated consistent and significant increases in average daily gain and daily feed intake for pigs provided with shaded wallows. Rectal temperatures and respiration rates were higher for pigs with the unshaded wallow. Garrett et al. (1960) also found that wallow temperature during the hottest part of the day was 12.2oC lower in a shaded wallow. Comparatively little use was made of an unshaded wallow after the water temperature reached 35oC. Sprinklers: Wet skin can release the heat stress of grazing pigs. A number of methods can be used to achieve this objective such as a wallow, water drips and spray. However, water sprays seems to be more effective than wallows (Culver et al. 1960, Table 16). McCormick et al. (1956) found that sprinklers increased daily gain from 45-144 g/pig. However, sprays are not effective in cool, rainy weather. Wallace et al. (1957) found that under Florida's hot dry conditions the use of a mist-type spray significantly increased rate of gain, especially when temperatures were above 32.2 oC. Ru and Glatz (2001) found that foggers were successful in reducing heat stress of grazing pigs, especially when they were set up in the shaded areas. McGlone et al. (1988) reported that at an ambient temperatures above 29oC, drip cooling decreased the weight loss of sows from 27 to 9 kg and improved litter weight gain from 1.47 to 1.85 kg/day during a 28-day lactation. Similarly, Maxwell et al. (1990) recorded a reduction in respiration rate and an estimated increase in milk yield of approximately 1 l/day for sows that were drip cooled when ambient temperature exceeded 26oC. However, pigs often root under the sprinklers especially when soil moisture is elevated. Table 16. Effectiveness of a wallow and water spray on the growth of swine (Culver et al., 1960) Treatment Variable I-Control II-Wallow III-Spray Number of pigs 12 12 12 Initial weight, kg 38.58 38.58 38.58 Final weight, kg 92.60 96.68 98.50 Total gain, kg 54.01 58.10 59.91 Av. Daily gain, kg 0.86 0.93* 0.95** Av. Daily feed, kg 3.09 3.27 3.41 Feed per kg. Gain, kg 1.63 1.60 1.63 * P<0.05; ** P<0.01 Housing/hut: Huts or shelters are crucial for preventing pigs from direct sun burn and heat stress, especially when shade from trees and other facilities is not available. McGlone (1987) also reported that for farrowing sows, the huts in paddocks might have some merit during very warm summer weather in temperate climates or in a tropical environment. However, the effectiveness of housing facilities on heat release largely depends on the ground vegetation, ground moisture and the materials used for the housing facilities because these affect ground temperature beneath the shade and thus affect the animal heat load. In addition a shade area may be designed in a way that permits maximum heat loss from the animal. Roof treatments which are satisfactory, include straw, wood, galvanised steel, aluminium or laminated polyethylene plastic. White-painted aluminium sheets were 9.4oC cooler than unpainted aluminium in the direct sun while white painted galvanised iron was 10oC cooler than unpainted sheets (Andrews et al., 1960). Feeding appropriate diets: The depression in feed intake and growth rate observed in heat stressed animals can be partially alleviated by altering the heat increment of the diet by lowering the dietary

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protein level and reducing those levels of essential amino acids which are excess to the animal’s minimum requirement (Waldroup et al., 1976). In a comprehensive experiment, Schoenherr et al. (1989 a, b) housed lactating sows at either 20 or 32oC and fed basal, high-fibre or high-fat diets. In the hot environment, increasing the energy density of the diet improved milk yield at all stages of lactation. Conversely, the addition of fibre in a hot environment depressed milk yield, and hence the weight of piglets at weaning compared to either the basal or high fat diets. Heat production associated with the microbial fermentation of dietary fibre in the hindgut account largely for the poorer performance of sows fed high fibre diets in hot environments. However, under grazing conditions, it is difficult to control the fibre intake of pigs although the high energy, low fibre diet can be used for free-range pigs. Nose rings: In some countries outdoor sows are fitted with nose rings to prevent them from uprooting the grass. Nose rings can effectively prevent the sows from rooting by causing pain in the nose. This reduces the risks of disease infection in pigs and nutrient leaching of the land. From the animal welfare point of view, nose rings under free-range condition allows the pigs to perform most of their natural behaviour patterns, but prevents them from engaging in rooting behaviour, an important behaviour activity for pigs to gain information about the surroundings (Studnitz and Jensen, 2002). Studies conducted in semi-natural conditions showed that sows spend 40–60% of their active time seeking food and exploring (Blasetti et al., 1988; Edwards et al., 1993), and rooting behaviour constitutes 10–20% of their active time (Stolba and Wood-Gush, 1984; Horrell and A’Ness, 1996; Berger et al., 1998). Nose rings may also restrict the foraging capability of pigs, especially when the sward is short. No information is available on the effect of nose rings on forage intake and grazing behaviour of free-range pigs. Mortality: It is well documented that free-range pigs have a higher mortality compared to intensively housed pigs. Many factors can contribute to the death of the piglet including crushing, disease, heat stress and poor nutrition. Leite et al. (2001) determined the causes of pre-weaning mortality in 106 piglets reared in outdoor system from October 1996 to October 1999. He found that crushing was the main cause of the piglet mortality (76.42%), followed by injury (13.21%) and other causes (diarrhoea, infection deformed and unknown factors) (5.66%). Mortality due to crushing was more frequent in the first 24 h after farrowing (37.74%). The mortality in piglets born in winter with birth weight of 1.5kg was 33.96%, and in litters from sows in third and fourth parity were 37.74 and 24.53%, respectively. However, after surveying 54 outdoor systems, Kongsted and Larsen (1999) found the average mortality rate (18.3%) for free-range pigs was similar to in indoor pigs (18.7%). Breed did not affect mortality rates and mortality was not correlated with temperatures nor with level of dry bedding. Mortality rate was lower when sows were moved to farrowing paddocks 10 days before farrowing compared with sows moved 0-6 days before. The mortality rates tended to be lower with increased grass cover and to be elevated when rainfall was higher. Performance of Free-Range Pigs The production performance of free-range pigs is strongly influenced by season, nutrition and management. The performance of growers and sows has been assessed by many researchers under different environmental conditions. Sows: Outdoor production systems for sows is common in a number of European countries. The numbers of sows housed outdoors has increased dramatically in EU in recent years, with 20% of the breeding herds in UK housed outdoors. The characteristics of the outdoor production systems include; 1) all sows are outdoors and loose during lactation, 2) the facilities for serving are either outdoors or indoors and the servings are based on uncontrolled natural services, controlled services, artificial inseminations, or a combination of these practices. All dry sows are loose-housed and in groups. The sows in outdoor systems are housed under different conditions in their complete reproduction cycle or at least in significant parts of it, compared to indoor sows. This means that outdoor housed sows are exposed to changes in the length of daylight (Perera and Hacker, 1984; Prunier et al., 1994), and variation in temperatures (Stansbury et al., 1987; Prunier et al., 1994). Thus it is difficult to compare

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the performance of outdoor sows between experiments and often the research outcomes are contradictory. For example, a recent study by Johnson et al. (2001) showed no difference in the performance of Newsham sows and their piglets housed indoors and outdoors (Table 17). Larsen and Jorgensen (2002) analysed sow records from three Danish and one Scottish outdoor herd and found that the average level of the reproduction cycle was 149.9 days between farrowings, 28.0 days from farrowing to weaning, 5.6 days from weaning to first recorded service and 116.2 days from first recorded service to farrowing. These are similar to performance observed in the indoor system. However, Oldigs et al. (1995 cited by Wulbers-Mindermann et al. 2002) reported that outdoor sows lost more backfat and weight during lactation. Table 17. Least squares means and standard errors for production performance of Newsham sows and piglets housed indoors vs outdoors over two parities from January to September 1999 (Johnson et al., 2001) Production measures Indoor Outdoor P-valuea Number of sows & litters 147 140 Pigs born (No./litter) 10.8 ± 0.10 10.5 ± 0.11 0.15 Pigs born alive (No./litter)

9.4 ± 0.49 9.4 ± 0.44 0.95

Still-births 0.9 ± 0.10 0.7 ± 0.11 0.15 Mummies (No./litter) 0.0048 ±0 0.0039 ±0 0.73 Days of lactation 23.8 ± 0.47 22.2 ±0.48 0.10 Piglets weaned (No./litter)

8.4 ± 0.41 7.6 ± 0.37 0.33

Mortality (%) 11.0 ± 1.61 11.8 ± 1.74 0.76 Litter birth wt (kg/litter) 19.7 ± 1.35 21.1 ± 1.48 0.22 Piglet birth wt (kg/pig) 1.9 ± 0.14 2.1 ± 0.15 0.29 Litter wean wt (kg/litter) 58.4 ± 2.96 53.3 ± 3.24 0.08 Sow start wt (kg) 216.4 ± 6.47 227.3 ± 6.79 0.08 Sow end wt (kg) 190.6 ± 3.59 186.1 ± 3.91 0.15 a P-value comparing indoor- and outdoor-reared piglets b Weight of sow on the day she entered the farrowing facilities and on the day she returned to breeding after piglets were weaned. The sow’s performance is affected by season, reflecting the influence of temperature. An evaluation of 341 farrowing records, collected over a 2-year period by Stansbury et al. (1987) showed that the number of splay-legged pigs and daily sow feed intake were directly affected by season (Table 18). Litters contained fewer splay-legged pigs per litter during the summer than during autumn or winter. Daily intake of sows was lower in the spring than in any other season. Total litter weaning weights were lighter in 30oC than in 18 or 25oC environments. Average individual pig weaning weight was higher in the 18oC environment than in the 25 or 30oC environments. Litter mortality was 8% and 7% lower in the 25oC than in the 18 or 30oC environments, respectively. High temperature (30oC) reduced daily sow feed intake and increased the body weight loss of sows. Sows in the 18oC environment took 2-3 days longer to come into oestrus after weaning than those in the warmer environment (Table 19).

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Table 18. Least square means and standard errors for sow and piglet performance by season (Stansbury et al., 1987)

Season Production variable Autumn Spring Summer Winter SEa P-value Number of litters 75 83 95 88

Litter weaning weight (kg) 56.67 59.03 56.84 58.18 1.16 0.44 Weaning number 8.6 8.7 8.6 8.5 0.13 0.48

Pig weaning weight (kg) 6.64 6.80 6.60 6.92 0.11 0.11 Mortality (%) 13.22 11.60 12.72 13.94 1.18 0.83

Splay-legged/litter 0.44d 0.32cd 0.17c 0.45d 0.08 0.04 Sow feed intake (kg/day) 6.48d 6.05c 6.56d 6.50d 0.13 0.02

Sow weight loss (kg/lactation) b 21.36 23.05 19.98 18.15 1.55 0.15 Weaning to oestrus (day) 6.1 4.9 5.6 4.8 0.44 0.13

a Pooled standard error of the mean, n=85. b Weight change from entering farrowing barn (pre-farrowing) to end of 28 day lactation.

c,d Means in the same row without a common superscript differ (P<0.05).

Table 19. Least square means and standard errors for sow and piglet performance in different farrowing house temperatures (Stansbury et al., 1987) Temperature (oC) Production variable 18 25 30 SEa P-value Number of litters 29 29 30 Litter weaning weight (kg) 63.23c 61.13c 52.38d 2.47 0.01 Weaning number 8.1 8.9 8.3 0.27 0.13 Pig weaning weight (kg) 7.82c 6.87d 6.40d 0.20 0.001 Mortality (%) 20.35c 11.97d 18.79c 2.29 0.04 Creep feed intake (kg/lactation) 3.13 3.04 2.61 0.74 0.88 Sow feed intake (kg/day) 6.46c 6.13c 4.20d 0.19 0.001 Sow weight loss (kg/lactation) b 3.14c 7.86c 24.21d 2.25 0.001 Weaning to oestrus (day) 7.3c 4.4d 5.3d 0.62 0.01 a Pooled standard error of the mean, n=85. b Weight change from entering farrowing barn (pre-farrowing) to end of 28 day lactation. c,d Means in the same row without a common superscript differ (P<0.05). Growing pigs: Many factors influence the performance of growing pigs in the outdoor environment. These include environmental conditions, quality of supplementary feed and forages, disease control and the nursing capability and parity of sows. With successful management, free-range pigs can grow as fast as indoor pigs. For example, Huiskes et al. (1999) found that outdoor pigs and indoor housed crossbred growing-finishing pigs had similar daily gain (757 vs 769g/d), feed intake (2.32 vs 2.35 kg/day) and feed conversion ratio (3.07 vs 3.05). The average carcass yield was similar (52.0 vs 51.3%), but percentage of pigs requiring veterinary treatment was 12.5% for outdoor pigs and 26.7% for indoor pigs. Pigs outdoors had fewer leg disorders than those housed indoors (10.8% vs 22.5%). Research conducted by Wulbers-Mindermann et al. (2002) demonstrated that outdoor piglets grew faster with less within litter variation in piglet weight at weaning than indoor piglets, although they had no access to piglet creep feed given to indoor litters. The authors believed that this result may be due to the greater willingness by the sow to nurse her litter because outdoor environment promotes the sow to invest more of her body energy into the rearing of her offspring, although no evidence shows that outdoor sows have a higher nursing frequency or a higher total milk yield. Wulbers-Mindermann et al. (2002) also suggested that the stronger immune system and the lower pressure of infection resulting from less animals per unit promoted growth of the outdoor pigs compared to indoor pigs. However, some researches have shown that free-range pigs took more days to reach target weight. For example, pigs reared from 25 to 105 kg required 16±1.2 (SEM) more days to reach market weight compared with confined pigs and the daily gain was lower than the confined pigs (916 ± 27 vs 1089 ± 27 g/day) (Sather et al., 1997). A similar result was reported by Sans et al. (1996). Daily gain from 40 to 140 kg body weight was low (384 g/day) for Gascony pigs reared in an outdoor system.

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However, it seems that piglet mortality is higher among outdoor herds than indoor herds, especially during the colder season with huts having no insulation. Large variations in management practices exist between herds, and therefore piglet mortality will vary. The survival of the piglet is more dependent on environmental factors (Wulbers-Mindermann et al., 2002) although the sow’s maternal behaviour is also associated with the mortality of piglets (Vieuille et al., 2003). However, management strategies for reducing piglet mortality are still not adequately developed for free-range pigs compared to indoor housing systems. The growth rate of the litter is also affected by season. Piglets grow quicker indoors during the cold season compared to outdoor systems (McGlone et al., 1988; Azain et al., 1996). The seasonal effect is more apparent in free-range system. The above authors found that during the cold season, outdoor sows were probably less active grazing and rooting on frozen ground due to the lower air temperatures, and shorter day length. Therefore sows might have spent more time inside the hut, conserving energy and nursing piglets. Wulbers-Mindermann et al. (2002) also reported that the multiparous outdoor sows have faster growing litters than primparous sows. This is due to the maternal experience in combination with an outdoor environment supplying the sows with good conditions to perform their maternal behaviour in such a way that it supports the piglet growth rate. Sather et al. (1997) compared the performance of growing pigs housed in confined or free-range systems during different seasons. While housing did not affect feed requirements during the summer, food consumption increased by 13.7% for free-range pigs during winter. Pigs in the confined environment consumed more feed than free-range-reared fed pigs in both winter and summer. During summer, free-range pigs were more feed efficient than confined pigs. Rearing pigs in free-range lots from 25 to 100 kg resulted in a reduction in growth rate and an increase in slaughter age, with a modest increase in feed conversion and in total feed consumption during the winter months compared with the intensive housing system (Table 20). However, Costa et al. (1995) reported that the rate of return on the total capital invested in the outdoor systems was close to 24%, 5-8% higher than the two traditional systems with fully or partially slatted flooring. Table 20. The effect of housing within season on production performance adjusted to an off-farm (finishing) weight of 105 kg (Sather et al. 1997) Season Contrast Summer Winter Main effect Confined Free-range Confined Free-range Season Housing Summer Winter Trait Mean SE Mean SE Mean SE Mean SE P>F P>F P>T P>T Weight on Testz

25.0 0.55 25.7 0.54 25.8 0.56 26.3 0.56 0.1659 0.2896 0.3648 0.5511

Weight on Testz

102 2.4 112 2.3 102 2.4 106 2.4 0.2637 0.0062 0.0055 0.2608

Age to market

168 1.2 185 1.2 159 1.2 175 1.2 0.0001 0.0001 0.0001 0.0001

Average daily gain

897 6.7 750 6.8 935 6.9 786 6.8 0.0001 0.0001 0.0001 0.0001

Feed conversion

2.81 0.069 2.76 0.076 2.86 0.069 3.18 0.066 0.0501 0.0922 0.8766 0.0132

Daily food intake

2.49 0.047 2.17 0.052 2.65 0.047 2.52 0.045 0.0037 0.0010 0.0038 0.0906

Total food consumption

226 5.3 229 5.3 222 5.8 252 5.1 0.1335 0.0185 0.6775 0.0150

Number of pigs

35 35 36 36 34 34 34 34

Number of pens

3 3 3 3 3 3 3 3

z Unadjusted for off-farm weight. Welfare and behaviour of free-range pigs Pigs were known as lazy animals because of their habit of lying motionless for long periods in shaded areas and as unclean animals because of their preference for mud wallows in warm weather. It is now recognised that the pig uses this behaviour to instinctively protect itself against hyperthermia, sunburn and possible heat shock by the use of shade and evaporative cooling (Culver et al., 1960). This is particularly important for pigs foraging outdoors.

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Behaviour of outdoor pigs vs indoor pigs: Pigs reared outdoors have shown calmer behaviour (Warriss et al., 1983). Their calmness and increased exercise behaviour make free-range pigs less susceptible to stress. Aggressive interaction frequencies during feeding were found to be lower compared to earlier indoor studies (Jensen and Wood-Gush, 1984). The lower A/R-ratio (the total number of observed "attacks" divided by the total number of observed "retreats") of 0.13 ±0.10, compared to 0.4, 3.6 and 8.2 in the 3 indoor systems, indicates a low aggression level and a stable social system in the free-ranging group (Jensen and Wood-Gush, 1984). Wood-Gush and Stolba (1982) observed the behaviour of pigs in a park, consisting of an enclosure of 1.3 ha containing a small pine copse, gorse bushes, a stream and a swampy wallow. Pigs made a large number of communal nests for sleeping. They were some distance from the feeding site, were protected against the prevailing winds and had a wide view that allowed the pigs to see anything approaching the nest from most directions. Before retiring to the nest, the animals tended to bring nesting material for the walls and to rearrange the nest. This was not a coordinated activity but most pigs performed it. Some individuals carried more nesting material than others. On leaving the communal nest in the morning, the animals walked at least 5 metres before urinating and defaecating, the latter mainly on paths between bushes. In autumn, 51% of the day was devoted to rooting. Much behaviour took place in the border of the wood and the open vegetational zone. Here trees were used for marking, in which the facial area is rubbed, sometimes in one direction only. Special relationships were found, e.g. a pair of sows might join together several days after farrowing and forage and sleep together. However, no cross-suckling has been seen in the litters of such animals. Members of a litter of the same sex tend to stay together and to pay attention to one another's exploratory behaviour. Aggressive play appears to be more common amongst the young males. Both sexes showed manipulative play. Farrowing nests were constructed by the sows, usually some distance from the communal nest, and the site chosen was usually under a branch or fallen tree. After farrowing, the nest was protected for about five days. From about that time, the sow tended to leave her litter for varying periods and piglets began to explore their environment. Guy et al. (2002) reported that pigs in outdoor paddocks spent the majority of time inside the shelter hut. When not in the hut, rooting and chewing at the floor and surroundings, and moving around the paddock accounted for a large part of their activity Webster and Dawkins (2000) determined the effect of outdoor and indoor lactation on the development of pig behaviour at weaning. On day 1, 8, 15 and 57 post-weaning it was found that from weaning to day one post weaning, outdoor bred pigs feed more than indoor pigs. From days 8-57 post weaning, outdoor pigs rooted more than indoor pigs (22.5 vs 24.7 observations/pen/day). These findings suggest that the lactation environment has a significant effect on the behaviour of pigs in their subsequent growing environment. Johnson et al. (2001) found that outdoor piglets spent more time engaged in play activity than indoor-reared piglets (Table 21). Webster (1997) also reported that outdoor born piglets at day 15 spent less time in contact with the sow and more time directing their rooting toward the soil, plants, and straw available in the pasture compared with indoor born piglets. Pigs reared in a poor environment (intensive, in a farrowing crate) behave more aggressively. The subordinates of these pigs also develop chronic social stress indicated by the delayed onset of puberty, reduced daily gain and elevated basal cortisol levels. The deterioration in social skills lead to increased social stress and a failure to cope with stressors in general (de Jonge et al., 1996). However, Warriss et al. (1983) reported that the rearing environment of pigs (confined vs free-range) had no effect on indicators of stress (blood cortisol levels and adrenal gland ascorbic acid levels). Their research also demonstrated that confinement-reared pigs were more difficult to load into trucks than free-range pigs, which was supported by Barton-Gade and Blaabjerg (1989)’s findings. Grandin (1989) also believed that environmental enrichment (access to toys, outdoor rearing) reduced excitability in pigs, which in turn allowed easier handling and less stress prior to slaughter.

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Table 21. Least squares means and standard errors for behaviour performed by Parity-2 Newsham piglets indoors vs outdoors from January to March 1999 (Johnson et al., 2001) Environment Behavioural measures Indoor Outdoor SE P-valuea Number of sows 20 20 Standing (%) 15.7 22.1 2.38 0.23 Lying (%) 72.2 68.1 3.11 0.19 Sitting (%) 3.3 3.4 0.64 0.94 Walking (%) 5.2 10.1 1.72 0.02 Nursing (%) 20.3 27.5 2.02 0.03 Playing (%) 1.7 5.0 1.26 0.046 Out of sight (%) 0.21 0.74 0.26 0.08 Contact with sow (%) 38.8 39.2 2.78 0.94 No contact with sow (%) 61.0 60.0 2.86 0.84 a P-value for comparison of indoor- and outdoor-housed lactating sows. P-values are based on analysis of transformed data. Outdoor pigs are often supplied with bedding materials such as straw which encourages pigs to spend more time on rooting and foraging and less time on tail-biting and other stereotypic behaviours. Interaction between genotype and housing system did not occur to any major degree (Guy et al., 2002). Olsen (2001) examined the effect of roughage (including straw) and access to shelter in pens with outdoor runs on oral activity towards penmates and other environmental stimuli. He found that access to a combination of roughage and shelter reduced penmate-directed oral activities. However, access to roughage in particular reduced redirected oral activities and skin lesions. The behaviour of outdoor sows: After sunset, outdoor sows reduce their activities and remain lying during the night. In hot seasons, sows have a reduced intake, but the intake can be increased in cooler seasons (Quiniou et al., 2000). Santos Ricalde and Lean (2002), however, suggested that an increase in grazing behaviour can occur during the night. Generally outdoor sows are more active than indoor sows (Johnson et al., 2001, Table 22). During the first few days after parturition the outdoor sows often leave the hut mainly for defecating and urinating, eating and drinking. Csermely (1994) reported that during the first 2 days after farrowing, the feral sow spent 76% of her time lying in her nest, but from day 3 until weaning decreased her lying time to 42% and moved a greater distance (>10) away from the nest. Jensen (1994) noticed that sow behaviour significantly changed during the first 4 weeks of nursing. Foraging and locomotion increased whereas lying, nursing, and contact with piglets decreased. Sows soon find the older piglets increasingly stressful to manage and in a natural setting choose to spend more time away from the litter. Petersen et al. (1990) studied the behaviour of sows and piglets during farrowing under free-range conditions. It was concluded that pigs, in spite of domestication, are behaviourally well adapted to cope with the problems associated with farrowing under free-range conditions. The general behaviour and also the birth data of the piglets in their study were not so different from what has been found in indoor housing systems (English and Smith, 1975). The females showed behaviour which may promote social bonding. The observation that pigs sniff at the young of the females is similar to observations in wild boar (Gundlach, 1968 cited by Petersen et al., 1990), in intensive housing systems (Jones, 1966) and in free-range domestic sows (Jensen, 1986).

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Table 22. Least squares means and standard errors for behaviours performed by Parity-2 Newsham sows indoor vs outdoor from January to March 1999 (Johnsen et al., 2001) Environment Behavioural measures Indoor Outdoor SE P-valuea Number of sows 20 20 Active (%) 9.1 27.9 2.76 <0.001 Lying (%) 90.9 72.1 2.76 <0.001 Sitting (%) 3.2 1.9 0.66 0.34 Drinking (%) 4.42 1.4 0.60 0.004 Feeding (%) 1.4 3.0 0.92 0.09 Nursing interval (min.) 40.1 42.2 2.47 0.30 a P-value for comparison of indoor- and outdoor-housed lactating sows. P-values are based on analysis of transformed data. Feeding level and behaviour of outdoor pigs: The activities of pigs, especially those associated with foraging behaviour are affected by feeding levels. For example, Santos Ricalde and Lean (2002) reported that the time spent grazing, grazing activities and distance walked reduced significantly with increased energy intake. Extremely high temperature had a greater effect on grazing behaviour and body temperature than energy intake in pregnant sows kept outdoors under tropical conditions. Stern and Andresen (2003) studied the foraging behaviour and daily weight gain of outdoor growing pigs given 100 or 80% of the indoor recommended feed allowance. While the mean daily weight gain was higher for the high feeding level, pigs on the high feeding treatment spent most of their time on rooting (Table 23). It was surprising that time spent on foraging was not affected by feeding level. However, a study with twenty-four primiparous sows showed that time spent grazing, grazing activity and distances walked reduced significantly with increased dietary energy intake from 19 to 33 MJ DE/day. Rectal temperature increased significantly as energy intake increased. Increases in feed intake during pregnancy reduced grazing behaviour during daytime and increased the rectal temperature (Santos Ricalde and Lean, 2002). Studies under indoor conditions suggest that feed with inadequate crude protein content can induce rooting behaviour (Jensen et al., 1993) and pigs may select a diet suitable for their needs if given the choice (Kyriazakis and Emmans, 1991). However, the extremely high ambient temperature had a greater effect on grazing behaviour and body temperature than energy intake in pregnant sows kept outdoors under tropical conditions Table 23. Frequency of behaviour in relation to feed level corresponding to 80 or 100% of indoor recommendations (Stern and Andresen, 2003)

Feed level Behaviour 100% 80%

Level of significance

Rooting 5.8 8.5 ** Grazing 30.0 33.6 n.s Other activities 9.7 7.1 * Passive (outside the hut) 12.1 12.1 n.s In hut 42.4 38.7 n.s Least square means and level of significance. *p<0.05, **p<0.01, n.s., p>0.05. Temperature and behaviour of outdoor pigs: As mentioned in the previous section, pigs are very sensitive to the ambient temperature. High temperature has a strong effect on pig’s behaviour, especially the activities associated with the wallow. It was observed that rooting in wallow water and making bubbles in wallow water were found to increase with increasing temperature. The duration of behavioural activities towards the wallow water increased when the ambient temperature exceeded 15oC. Olsen et al. (2001) suggested that at this temperature the behaviour gradually changes towards temperature regulatory associated behaviour. However, other researchers found that in outdoor kept pigs, wallows are used regularly when temperature exceed 18–19 oC (Stolba and Wood-Gush, 1989; Andresen and Redbo, 1999). Pigs also lay in the wallow even at temperatures below 0oC — but not for very long, suggesting that wallowing may play a role in care of pigs’ skin and hair (van Putten, 1978). Also the duration of rubbing the trunk and the hindquarters increased with increasing

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temperatures. This might indicate that these behavioural comfort activities are related to the temperature regulatory behaviours (Sambraus, 1981 cited by Olsen et al. 2001). There were no relationships between temperature and rooting behaviour in outdoor growing pigs (Andresen and Redbo, 1999). Above 5oC, the ambient temperature has little effect on the shelter-seeking behaviour of the pigs and radiant temperature appears to have no effect. Rain increased the time spent on chewing, sucking or making rooting movements towards penmates in the indoor part of the pen, and biting or rooting towards pen hardware in the outdoor run. Rain increases oral activities towards penmates regardless of housing system. Rain also encourages tail-biting which is undesirable from both an economic and welfare point of view. However, further studies are required to reveal if oral activities towards penmates generally are affected by rain. Buckner et al. (1998) also found that on rainy days, the pigs spent less time outside their huts. Air movement appeared to affect the pigs’ choice of habitat to the greatest degree, with pigs usually choosing to avoid the windiest parts of their paddocks. Although the growing pigs sought shelters more often when the temperature fell below 5oC, this was well below their lower critical temperature of about 20oC, thus most of the time the pigs spent outside involved additional heat loss. Lying in deep straw with body contact was negatively correlated with temperature. Keeping pigs in straw is an effective way to stay warm (Geers et al., 1986). The duration of lying in deep-straw without body contact, and lying in all the other areas were positively correlated with temperature. These findings may suggest that lying with body contact in deep-straw is a significant way of staying warm, whereas lying in other areas of the pen and outdoor run are ways to increase heat-loss from the body. Stocking rate and behaviour of outdoor pigs: The behaviour of free-range pigs is associated with the area of the paddock and the herbage availability which is largely dependent on the stocking rate. The frequency of eating was 18% higher on the low stocking rate compared to the high stocking rate, whereas rooting (powerful and light rooting) and passive behaviour tended to be higher on the high stocking rate (Andresen and Redbo, 1999, Table 24). It seems grazing was preferred to rooting, when herbage still was available. The tendency for a higher incidence of rooting on the smaller plots might thus be a substitute for above-ground foraging (Andresen and Redbo, 1999). Table 24. Proportion of recordings of behavioural elements in relation to stocking rate (Andresen and Redbo, 1999) Stocking rate Behaviour 5pigs/50 m2 5pigs/100 m2 P value Significance Powerful rooting 0.089 0.062 0.079 tendency Light rooting 0.076 0.050 0.072 tendency Eating 0.392 0.569 0.009 ** Nosing 0.036 0.022 0.005 ** Other activities 0.139 0.096 0.026 * Inactive 0.265 0.199 0.096 tendency Rooting 1 0.165 0.111 0.067 tendency **P<0.01; *P<0.05; tendency: P<0.10; 1 Rooting = powerful rooting + light rooting Urinating behaviour of grazing pigs: It seems that pigs prefer to dung in light and draughty areas (Randall et al., 1983) and away from their sleeping area (Stolba and Wood-Gush, 1989). Pigs also dung in the wallow because they prefer to excrete in wet areas (Fritschen, 1975). In sows, Sambraus (1981 cited by Olsen et al. 2001) found that defecation and urination was done before wallowing, but he found only a few cases of defecating and urinating in the wallow. Hacker et al. (1994) stated that pigs drink, urinate and defecate in a close sequence. Olsen et al. (2001) observed that pigs placed more than 75% of the dung in the outdoor runs and about 50% in the wallow. The pigs excreted away from the roughage and their lying area and shade. Stern and Andresen (2003) found that defecation and urination were most frequent in newly allotted areas, followed by the dwelling area. This suggests that successive allocation of new land gives rise to a distinct foraging area, which also is frequently used for excretory behavior. Olsen et al. (2001) suggested pigs do not prefer to dung in busy areas because

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of the so-called ‘unstable posture’ during excretion as proposed by Randall et al. (1983) and Aarnik et al. (1997). Teeth clipping and behaviour: Delbor et al. (2000) studied the effect of teeth clipping and iron injections on skin lesions and growth of piglets born in the outdoor system. Leaving the teeth intact increased piglet growth rate between birth and weaning (+0.016 kg/day; P<0.05) and there was no significant difference from weaning to 63 days. Leaving the teeth intact was associated with an increase in the severity of skin lesions at days of age, but it disappeared at weaning. It is concluded that the procedures commonly used in outdoor systems, teeth clipping and iron injection, do not improve piglet performance. However, teeth clipping may have an effect on behaviour and forage intake of free-range pigs. Disease Control A number of researchers have reported that pigs in outdoor units have better health than indoor herds, have fewer respiratory problems and a lower incidence of enteric disease (Thornton, 1990; Tubbs et al., 1993). On the other hand, deaths from swine urogenital disease (32.4%), heart failure (21.8%) and locomotor problems (33.1%) have been reported to be higher in outdoor production (Karg and Bilkei, 2002). Nansen and Roepstorff (1999) summarized the helminthes found in indoor and outdoor pigs (Table 25). It is obvious that outdoor pigs have a higher parasite burden, which increases the nutrient requirement for maintenance and reduces feed utilization efficiency of the free-range pigs. The high numbers of parasite in free-range pigs may also risk the image of free-range pork as a clean and safe product. Rodriguez-Vivas et al. (2001) also reported that Isospora were prevalent in 94 and 41% of the sows in the outdoor and indoor systems, respectively. Sows in the outdoor system have a higher excretion of oocysts from Isospora than sows kept indoors. Leite et al. (2000) measured that the incidence of internal parasites in outdoor pig production, after use of some husbandry practices without anthelmintic administration. Over two experimental years, 83% and 78% of the faecal samples were positive for eggs of Strongyloididae and coccidia oocysts, respectively. Ectoparasites or erysipelas were not found in the adults and no endoparasites were found in the piglets. The helminth infections will be more prevalent for pigs under organic production systems which rely heavily on grazing without using antibiotics and other chemicals. In a short to medium term perspective, integrated control may combine grazing management with biological control using nematophagous micro-fungi, selected crops like tanniferous plants and limited use of antiparasiticides. Table 25. Helminths found in pigs in relation to type of management (Nansen and Roepstorff, 1999)

Domestic pig Helminth

Wild boar Outdoor Indoor (extensive) Indoor (intensive)

Ascaris + + + + Oesophagostomum + + + (+) Trichuris + + + (+) Strongyloides + + + Hyostrongylus + + (+) Metastrongylus + + Stephanurus + (+) (+) Ascarops + (+) Physocephalus + (+) Macracanthorhynchus + (+) Trichinella + (+) (+) Taenia + (+) Schistosoma + (+) Fasciola + (+) Dicrocoelium + (+) The number of parasites in the paddock varied with the season, which mainly reflects the sensitivity of parasites to temperature. Many eggs deposited during summer may die rapidly due to high temperatures and dessication. Some eggs deposited in cold months by foraging pigs cannot survive through lower temperatures, more moisture, and greater sequestration of eggs in the soil by rain and

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earthworms. For example, Larsen and Roepstorff (1999) found that A. suum and T. suis eggs, which are very resistant to environmental factors, may be subjected to a high mortality when eggs in faeces are exposed to desiccation and fluctuating temperatures during a dry summer (Larsen and Roepstorff, 1999). Oesophagostomum eggs deposited on a pasture in the winter will die (Larsen, 1996) although some infective larvae do survive outdoors during winter in temperate regions (Haupt, 1969 cited by Roepstorff and Murrell, 1997b). Roepstorff and Murrell (1997b) reported that both O. dentatum and H. rubidus were very sensitive to environmental factors and significant transmission occurred only under the most favorable conditions. Transmission was severely reduced during low temperatures in winter. Mejer et al. (2000) and Thomsen et al. (2001) found that O. dentatum became completely eradicated from heavily contaminated pastures, but Petkevicius et al. (1996) showed a significant winter infection of O. dentatum larvae. This suggests that larval survival depends upon weather conditions in combination with the relevant physical/biological factors in the pig facility (Roepstorff et al., 2001). For example, continuous grazing actually reduced transmission of O. dentatum and H. rubidus because of the reduction in vegetation although this grazing system has adverse environmental effects (Smith, 1979; Mejer et al., 1998). Roepstorff and Murrell (1997a) revealed that A. suum and T. suis eggs are much more resistant to environmental factors than free-living infective larvae of pig parasites such as Oesophagostomum dentatum and Hyostrongylus rubidus. Control of these parasites in outdoor pigs will present more difficult challenges than for parasites transmitted by free-living larvae. Grazing management: Diseases can be controlled to a certain degree by grazing management. Provision of clean (ungrazed) pasture and cleaning of any permanent facilities for each batch or production year are necessities but may not exclude the build up of infections. The time needed for resting pastures between batches to prevent transmission is also debatable. Thus frequent rotation is required although most farmers are keeping their pigs for a long period on a plot before rotating. Roepstorff et al. (2001) suggested that yearly rotation might not be sufficient in the control of parasites with long-lived eggs, such as A. suum, and that a pasture rotation scheme must include all areas, including housing where incidence of parasites is greater than other areas. Nansen and Roepstorff (1999) suggested that the controlling strategies for outdoor pigs against helminth infections should include pasture rotation, mixed or alternative grazing with other animal species, and the integrated use of anthelmintics. It is clear that the anthemintic treatment alone cannot completely control the helminthes since the animals will inevitably be infected on the contaminated pastures. The above studies indicate a need for a long-term research on transmission patterns of resistant, long-lived, but slowly developing eggs, like those of A. suum. Roepstorff et al. (2001) pointed out that multi-year rotation strategies should be adopted because the eggs survive in considerable numbers from year-to-year. However, no such strategies have been tested in practice and further research on practical pasture management in the control of pig helminths in extensive outdoor systems is required. Stocking rate: Stocking rate is considered to be an important factor in grazing management (Bransby, 1993; Thamsborg et al., 1999). The development of more intensive systems for animal production on pasture tends to raise the stocking rate. However, there are no recommendations for an optimum stocking rate for free-range or organic pig production systems. Generally a lower stocking rate is maintained on organic farms as a proportion of the grazing area has to be used for nitrogen-fixing plants, particularly clover, when commercial fertilizer is not used. Animals stocked at higher densities risk obtaining higher levels of gastrointestinal parasites. This has been shown in studies of sheep (Downey and Conway, 1968; Thamsborg et al., 1996) and cattle (Ciordia et al., 1971; Hansen et al., 1981; Nansen et al., 1988), but few studies have investigated the effect of stocking rate on helminth infections of free-range pigs in out-door areas. It is clear that the behaviour of pigs on pasture is different from ruminants because pigs often display rooting behaviour (Graves, 1984) and forage the dung patches. These behaviours may result in a higher risk of disease infection, with the magnitude being associated with stocking rate. Pigs stocked at high densities can rapidly turn the pasture into a mudded area (Roepstorff and Murrell, 1997a), which in combination with hot and dry weather may impede the development and survival of parasitic eggs and larvae (Larsen, 1996; Larsen and Roepstorff, 1999; Kraglund, 1999). In the first year of a two-year study

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using stocking rates of 17, 42 and 100 weaner pigs per ha, Mejer et al., (1998) found significantly higher faecal egg counts with higher O. dentatum worm burdens at the higher stocking rate. However, stocking rate did not correlate with A. suum and T. suis infection levels. In another study on the dynamics of parasites of free-range pigs at different stocking rates, Thomsen et al. (2001) revealed that the percentage of grass cover was reduced considerably at the high stocking rate (576 m2/pig) in comparison to the other stocking rates (100 and 240 m2/pig). The O. dentatum faecal egg counts and worm burdens were significantly higher in pigs at the highest stocking rate, but O. dentatum did not survive the winter. However, the transmission of T. suis was not influenced by stocking rate, but T. suis and A. suum eggs are still expected to constitute a high risk of infection on intensively used pastures where eggs may survive for years. It was also found that the effect of stocking rate on faecal egg counts and worm burdens was not linear because the infection levels at the low stocking rate were not lower than they were at the medium stocking rates. Thomsen et al. (2001) also pointed out that at high stocking rates, much of the grass disappeared leaving large areas with very short grass or bare soil. In combination with hot and dry weather, this may have provided poor conditions for the development of parasitic eggs and larvae. This further indicates the complexity of parasite transmission for free-range pigs. Nose rings: To avoid the damage to the grassland, it is common to apply a nose-ring to sows in outdoor herds, thereby reducing their rooting behaviour. This strategy will also assist in the parasite control for free-range pigs as both Oesophagostomum larvae (Larsen, 1996) and Ascaris and Trichuris eggs (Larsen and Roepstorff, 1999) survive well in soil. Roepstorff et al. (1992 cited by Thamsborg et al. 1999) suggested nose-rings could be a contributory factor to the very low infection levels found in several Danish outdoor sow herds not using anthelmintics. However, a recent trial failed to show any significant effect of nose-rings on helminth transmission (Mejer et al., 1998). A study of mixed (and alternate) grazing with nose-ringed sows and heifers, showed promising results in controlling Ostertagia infections in the cattle whereas little effect on the nematode infections of sows were noted (A. Roepstorff and J. Monrad, unpublished data). The lush grass surrounding the fecal pats typical of cattle grazing was absent due to the sows grazing and spreading and eating the cattle faeces. In warm moist environments, however, it cannot be excluded that the spreading of faeces may lead to a higher herbage infection. Plant materials: The concept of using pasture species to minimise nematode infections in grazing pigs looks promising and the possibilities seem far from exhausted. Plants that can be grown locally and used as part of the normal feeding regime are most likely to be acceptable to farmers, particularly organic farmers. The plants can possibly be used in the supplementary diet or they can be grown in a mixture with grass and legume pastures in the grazing paddocks. In line with this, research into the usage of locally available herbs is required to assess their efficacy for controlling diseases. While these herbs used traditionally for therapy are unlikely to have serious side effects, caution needs to be applied in substituting existing well defined chemical anthelmintics with lesser known herbs (Danø and Bøgh, 1999). Dietary manipulation and feeding fungi: Several components in the diet may affect nematode infections but relatively few studies have been carried out in monogastric animals. In pigs, high levels of insoluble dietary fibres have resulted in higher establishment rates and better fecundity of O. dentatum compared to diets with similar protein and energy levels but rich in digestible carbohydrates and proteins (Petkevicius et al., 1999). However, A. suum infections were not affected. These findings may have important implications for the epidemiology of Oesophagostomum spp. in sows under free-range or organic farming conditions. In these production systems, pigs are usually permanently exposed to infection, and roughage, primarily fresh grass or whole grain silage is fed ad libitum. Interestingly, feed structure also affects bacterial infections as commercial pelleted feed increases the prevalence of salmonella compared to homegrown feed. In pigs, one field trial has shown significant reductions in acquired Oesophagostomum spp. and H. rubidus infections by adding fungus D. flagrans to the feed (Nansen et al., 1996). The effect of D.

41

flagrans in faecal cultures from pigs does not seem to be affected by different levels of insoluble dietary fibre in the feed (Petkevicius et al., 1998). Sustainability of Free-Range Pig Production Systems It has been recognised that free-range pigs are a resource in the animal and the cropping system. The grazing and rooting of pigs reduce external inputs for soil tillage and weed control in the cropping system. However, one of the key concerns from public for free-range pig production system is the impact on the environment. In the past, the pigs were held in the same paddock for a long period at a high stocking rate, which resulted in an apparent damage to the vegetation, a great nutrient load in the soil, nitrate leaching and gas emission (Worthington and Danks, 1992). To avoid this, outdoor pigs should be integrated in the cropping pasture system, the stock should be mobile and stocking rate related to the amount of feed given to the animals. Considerable research has been carried out to assess the distribution, losses and uptake of nutrient by crops in free-range pig production systems. Nutrient distribution in paddocks: The distribution losses and utilization of nutrients in the paddock in succeeding rotated crops were investigated after grazing by pigs (Eriksen, 2001; Eriksen and Kristensen, 2001; Williams et al., 2000). A significant correlation between soil inorganic N and the distance to feeding sites was found after the paddocks had been used by lactating sows for 6 months. Near to feeders, inorganic N levels became extremely high whereas 30-40 m from feeders some patches had N levels in the topsoil corresponding to the levels in the reference area without sows. In the following spring, only a minor level of inorganic N was still present in the top 40 cm of soil. Similarly, extractable P and exchangeable K in topsoil were affected by distance to feeders with the highest values close to the feeder. The nutrient load was high in the soil close to the hut. Although huge variations in dry matter production and nutrient content occurred in the succeeding potato crop, these were related to the distribution of nutrients (N, P, K) in the previous year, which explained 17% of the total variation in dry matter production. This suggests that a uniform distribution of nutrients should be obtained by manipulating the excretory behaviour of the sows and adjusting stocking densities to locally acceptable nutrient surpluses for an increased nutrient efficiency in outdoor pig production (Eriksen and Kristensen, 2001). Worthington and Danks (1992) estimated annual feed N inputs at 625 kg N/ha for systems stocked at 14 sows/ha. Nitrogen output in pig meat was at 119 kg N/ha, leaving a surplus of 506 kg N/ha. This large surplus will be returned to the soil via dung and urine excretion, as ammonium-N and organically bound N. Some of the ammonium N will be lost to the atmosphere by volatilisation, with the remainder converted by nitrifying bacteria to nitrate-N. The organic N will mineralise gradually over time to produce ammonium-N which will be converted to nitrate-N and contribute to the soil mineral nitrogen pool. The nitrate-N will be available for plant uptake, but will also be susceptible to loss from the soil either by leaching or by conversion to di-nitrogen (N2) and nitrous oxide (N2O) gas during denitrification. Denitrification and nitrogen leaching: The spatial distribution of denitrification activity in a 5 x 5 m grid in a grazed paddock compared to an ungrazed paddock was assessed by Petersen et al. (2001) immediately after the sows (32 sows/ha for 6 month) were removed in October 1997, and again the following March. Denitrification rates averaged 0.01 kg N/ha per day in the control paddock, and 0.5 kg N/ha per day for the grazed paddock in October, while the corresponding figures in March were 0.01 and 0.1 kg N/ha per day. The highest denitrification rates were observed around the feeder, and this is also the case for concentration of dissolved organic C and inorganic N in the soil. A similar result was reported by Eriksen (2001), who found that the inorganic nitrogen concentration in soil was uneven after sow grazing, with the highest values found near the feeding area. Ten metres from the feeding area, leaching losses were 500 ka of N/ha and 330 kg of N/ha for 16m over 18 months. The nitrate leaching was determined by using the suction cup technique. Petersen et al. (2001) also stated that both climate and management (position of huts and feeder) appeared to influence denitrification, which was estimated to be 69 kg N/ha per year, or 11% of the N surplus of this production system. Williams et al. (2000) examined the nitrogen losses from outdoor pig farming systems in the UK. Three types of management system were included in this study, current commercial practice (CCP) -

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25 dry sows/ha on arable stubble; improved management practice (IMP) (18 dry sows/ha) on stubble undersown with grass and best management practice (BMP) (12 dry sows/ha) on established grass. In the first winter, mean nitrate-N concentrations in drainage water from the CCP, IMP, BMP and arable paddocks were 28, 25, 8 and 10 mg NO3/L, respectively. On the BMP system, leaching losses were limited by the grass cover, but this was destroyed by the pigs before the start of the second drainage season. In the second winter, mean concentrations increased to 111, 106 and 105 mg NO3-N/L from CCP, IMP and BMP systems, compared to only 32 mg NO3-N/L on the arable paddock. Ammonia losses from outdoor dry sows were in the region of 11 g NH3-N/sow/day. Urine patches were the major source of nitrous oxide emission, with N2O-N losses estimated at less than 1% of the total N excreted. Nitrogen inputs to all the outdoor pig systems greatly exceeded N taking off by crop plus N losses, with estimated N surpluses on the CCP, IMP and BMP systems after two years of stocking at 576, 398 and 264 kg N/ha, respectively, compared with 27 kg N/ha on the arable control. These large N surpluses are likely to exacerbate nitrate leaching losses in the following seasons and make a contribution to the nitrogen requirement of future crops. It seems that maintaining a vegetative cover during the stocking period will limit nitrate leaching losses from outdoor pig farming. Rhizominous grasses such as creeping red fescue (Festcua rubra) and smooth stalked meadow grass (Poa pratensis) may be more resistant to trampling and rooting habits of the pigs than the ryegrass (Williams et al., 2000). Changes in management practice, such as moving pigs to a new paddock on an annual basis may also be necessary to minimise nitrate leaching losses by maintaining a grass cover. Ammonia emission: Ammonia losses from outdoor pigs (11 g NH3-N/dry sow/day) measured by Williams et al. (2000) were similar to those measured for grazing dairy and beef cattles (17 and 5 g NH3-N/animal/day). The nitrous oxide emissions measured from pig paddock were similar to annual losses of 0.5 kg N2O-N/ha measured by Carran et al. (1995) from low fertility pasture soils grazed by dairy cattle, indicating increasing production of outdoor pigs would probably have little impact on total nitrous oxide emissions from agriculture. Conclusion Due to public concerns on animal welfare of intensively housed pigs and the demand for free-range or organic products, more pigs will be reared under free-range systems where they can express their natural behaviours. However, it is well understood that pigs are sensitive to environmental conditions especially temperature. When the temperature is below the lower critical temperature, pigs must increase heat production through shivering and other metabolic processes to maintain body temperature. On the other hand, when the temperature is higher than its evaporative critical temperature, the evaporative heat loss of pigs begins to increase, particularly from the lungs, through increased respiration. Because pigs are not able to sweat, they are more sensitive to hot than cold conditions. Pigs exposed to temperatures above the evaporative critical temperature have a low feed intake, milk yield and poor reproductive performance and growth rate. Water drippers, sprays and wallows are effective in reducing the impact of ambient temperature and improve the production of free-range pigs. However, foraging pigs can also damage soils around these facilities and dung in the water, with a build up of parasite load. Currently a natural product (betain) has been approved to be effective in heat release and is available commercially. The use of this product or similar products in free-range pigs need to be assessed. Drinking water should be always available for free-range pigs. This is particularly important for pigs in a hot environment. However, most pig producers ignored the quality of water. Under free-range system, water troughs are often accessible to wild birds and contaminated with dust, resulting in a high potential for disease transmission. This high temperature may cause a low water intake as found in intensively housed pigs by Cargill et al. (2001). Thus the strategies for cooling water in summer should be developed for free-range pig production system. The free-range pig production system has been successful for many farms under different environments although some farms have failed to be sustainable. Most farms are keeping their pigs in the same location for many years before rotating, frequently with a high stocking rate with a high

43

output per unit of land area. This practice has resulted in a degradation of vegetation and the build up of nutrients, which is a cause for great concern to the public. Current research by Ru and Glatz (2001) has shown that free-range pigs can be incorporated into a crop-pasture rotation system where pigs can play a role that sheep currently play in this system. This system requires a low stocking rate and frequent rotation. It was demonstrated that free-range pigs had had a similar effect on soil fertility and weed population although pigs consumed less pasture than sheep. However, the sustainability of this system requires further assessment, especially the optimum stocking rate and the most suitable pastures for this system under different soil types. Disease control is a major task for free-range pigs although some researchers have shown that free-range pigs are healthier than indoor pigs. The studies on the dynamics of parasites in free-range system clearly showed that the prevalence of parasite infections is influenced by season (temperature), stocking rate and grazing management. Under current production systems, except for organic farms, regular use of anthelmintics alone is the most common control method, unfortunately sometimes the only control intervention. It is apparent that an integrated parasite control system is more efficient under practical farming conditions. These include, 1) the purchasing of pigs from intensive indoor herds to limit the risk of introducing parasites, 2) frequent rotation (cropping) to prevent the build up of parasite, 3) mixing grazing with other livestock species such as cattle, 4) dietary manipulation, 5) the use of micro-fungi as biological control agents and incorporation in the pasture, plant species which have an effect on nematode infections, and 6) use of nose rings to prevent pigs from ingesting soils which often have a high parasite load. Future research in this area should include the identification of ‘new’ parasitic problems in free-range pigs and assessment of risk factors and their impact on health and production in organic farming. Acceptance of a certain degree of production loss without compromising welfare could be an option. An important issue is the risk assessment of parasitic zones in large outdoor pig rearing units. High mortality of free-range piglets is noticed by many farmers and researchers. Many factors contribute to the high mortality. These include high disease infections, variable environmental conditions and the behaviour of sows. It is clear that free-range sows have a better nursing capability and most of the deaths of piglets is caused by crushing. One of the major concerns for the community on free-range pigs is the emission of ammonia. Currently most research has been undertaken to assess the ammonia level in sheds where pigs are housed intensively. Little data is available on the ammonia released from free-range pigs. While it is clear that the total ammonia released to the air is dependent on the number of pigs in the paddock, the data on ammonia emission will assist farmers to establish the optimum stocking rate from an air quality point of view for the community.

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Methodology Management Committee The project was conducted under the direction of Industry representatives including Maggie Beer (gourmet food specialist and marketer), Peter Jones (Eco-Shelters, Australia), Christine Ross (free-range pig specialist) and Meg Parkinson (VFF President, Free-Range Egg Producers Association). During the project there was a conference call conducted to obtain advice from the committee. Throughout the project results of the work were e-mailed to the committee. Project Rationale The rationale for this work was to determine if pigs and poultry could be used to graze the surplus forage in the pasture/cropping rotation on the Roseworthy Campus farm. There were three phases to the project. Phase 1 (Year 1): Animals foraged on surplus pasture forage in late stage of the pasture growing season. Animal production was monitored including agronomic measures. This was followed by a cropping phase to determine yield of wheat after the animals had grazed the pasture. Phase 2 (Year 2): Pigs and poultry grazed the wheat stubble with monitoring of animal production and agronomic measures. Phase 3 (Year 3): Pastures were allowed to regenerate and animals grazed the pasture throughout the growing season. Use of animals Animals were only allowed access to the pasture and crop stubble for 4 months and then sold or housed in the ecoshelters while the next phase in the cropping/pasture program was being implemented. Paddocks Two 4 ha paddocks were used for this project, located opposite the main entrance to Roseworthy Campus in East 1 and East 2 paddocks. One paddock was used to establish the pig free-range facility and the other was for the poultry free-range facility. The facilities were approximately 1 km apart. Medic pastures were established in May 2000, prior to the commencement of the project in Sept 2000. Pig Facility For the pig trials, an Eco-shelter (3 m x 3 m) was built in the centre of a 4 ha paddock. The ecoshelter had four internal pens of equal size each capable of housing up to 10 grower pigs. The paddock was fenced into 8 plots each with an area of 0.5 ha. The paddocks were sown with a medic pasture. The first phase (or year 1) of the experiment commenced with the four plots being grazed by pigs at a stocking density of 16 pigs/ha and the other four grazed by sheep (16 sheep/ha). The sheep did not have access to the shelter and were used to provide the comparison with traditional agriculture. The pasture production, soil fertility, weed population, penetrometer values and pig production were monitored during the season. At the conclusion of this grazing period the paddocks were sown with wheat. The weed population, soil fertility, yields and quality of wheat was determined. After the harvest, in year 2 of the trial, grower pigs were located back into the paddock to forage the stubble, spilt grain and weed seeds. The population of weeds and insects were monitored. In year 3 (final phase) of the project, sheep and pigs grazed regenerated annual medic pasture. Pigs were supplemented with compound feed. The same experimental design was used as previously in

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phase 1 of the experiment. Likewise pasture production, soil fertility, weed population and the production of pigs were monitored during the season. Poultry Facility The experimental layout and the variables measured were the same as the pig trials. For the poultry trial in paddock 2, an Eco-shelter (located in the centre of the paddock) was divided into 4 sections each containing 55 hens. The paddock was fenced into 8 plots with 0.5 ha/plot. Sheep grazed four plots and the other four plots were foraged by poultry. The pasture production, hen production, soil fertility, weed and insect population were evaluated. In the second year, the paddock was sown with wheat. The measurements were the same as those conducted in the second year-pig trial. After harvesting the wheat, free-range poultry were moved into the paddock to forage the insects, crop residue and weeds. The population of weeds and insect were monitored. In the third year, regenerated annual medic pasture was grazed by poultry. Throughout the grazing trial hens were provided a layer ration with half their daily allocation (55 g/bird) fed in the morning and the other half (55 g/bird) in the evening when birds were locked in the shelter over night. Measurements Sampling: Each paddock was divided into 3 zones using fence posts as the marker. For sampling forage and soil, a random number of steps were stepped out from the markers and a quadrat (1/10 m2 ) placed on the ground. All forage materials above ground level were cut with scissors and collected with four samples being taken in each zone and placed in labelled brown paper bags. In each zone, an enclosure (0.6 m x 0.6 m) was set up to exclude both birds and pigs foraging and was used as the control zone. Forage samples were cleaned by removing dirt and faeces, then weighed and dried at 80 °C in an oven to determine total herbage weight or dry matter weight. Categories Each weighed sample was separated into crops, pasture, weeds, seeds, snails, pods and rubbish (any dirt, faeces and stone) and then weighed. The classification used was as follows;

1. Pasture: herbage plants and weeds. 2. Crops: seed, broadleaf and narrow leaf weeds. 3. Weed: legumes and weeds. 4. Grains: A 1 kg sample of wheat was screened with a 2mm rotary screen and small grain (%),

ryegrass (%), other weeds identified including salvation Jane, radish, brome and mustard. 5. Insect: adult/pupal/larvae, mites, beetles, bugs, flies, cockroaches and ants.

During the harvest, crop yield was measured by harvesting, cleaning and weighing the total seed yield from all paddocks. The yield was calculated as tonnes/hectare. Penetrometer In each zone a random number of steps were taken from the markers and the penetrometer probe inserted into the soil. Seven readings were taken in each zone (6+1 control). Production Pig live weight (before and after grazing), carcass weight and backfat measurements were obtained. For hens, egg production and mortality was recorded daily while live weight and egg weight were measured monthly. Chemical composition One-third of each herbage sample from four samples was combined and milled through a 1 mm sieve for dry matter and chemical analyses. Dry matter (DM) was determined by drying samples for 2 hours in an oven at 105oC. Ash was determined in a muffle furnace at 550oC for 6 hours. Organic matter

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was calculated by the difference between DM and ash. Crude protein was determined by using Leco 2000. Soil pH (in water and in 0.01M CaCI): Twenty gram (20 g) of air-dried soil (sieved < 2mm) was placed into 70ml Sarsdet vials. Fifty (50) ml of deionised water was added and tube was shaken for one hour end-over-end. The sample was allowed to settle on the bench for 20 minutes. The pH was recorded. Following the pH reading in water, 2.5ml 0.21 M CaCl2 solution was placed into each vial, to obtain a 0.01M CaCl2 solution. This solution was shaken for 15 minutes and then allowed to settle for 20-30 minutes. The pH was recorded. Soil Nitrate_N/Ammonia_N: Twenty (20) g air-dry soil (<2mm) was placed into a 250 ml plastic extraction bottle and 100ml 2M KCI extracting solution added. The solution was mechanically shaken end-over-end at 25°C for 1 hour. Then soil extracts were allowed to clear and a known aliquot filtered (Whatman No.42) for analysis. Nitrate and Ammonia To determine the mineral-N (Nitrate_N and Ammonia_N) fractions in soil extracts, a dual channel Perstop Analytical Alpkem AutoAnalyser was used. This system simultaneously measures NH4

+-N and NO3

--N/NO2--N by automated colorimetric procedures. The NO3

--N + NO2--N was measured by

the reduction of nitrate to nitrite using cadmium metal in the form of an Open Tubular Cadmium Reactor and the subsequent colorimetric determination of total nitrite nitrogen utilised a modification of the Griess-Illosvay reaction. The determination of NH4

+-N was obtained by using a modification of the Berthelot Indophenol reaction by replacing hypochlorite with Dichloroisocyanuric acid (DCIC). Egg taste test procedure Eggs were obtained from birds in the free-range facility and also from the same strain and age of bird from a nearby farmer with caged birds. Scrambled eggs were prepared by cooking in water to prevent any taste being imparted from cooking oil. Staff in the Animal Science Department and the PPPI were chosen at random with no notice and asked to sample some bite sized portions of scrambled egg and make comment on whether the flavour, colour and texture of the scrambled egg they consumed was very poor, poor, average, good or excellent. Sixteen staff agreed to sample the eggs. The origin of the cooked egg was not provided. Pork taste test procedure A leg of pork was obtained from a processed pig foraging on both the barley and medic pasture and from a pig of the same age from the Roseworthy commercial intensive piggery. The leg was roasted in an oven bag without any addition of flavours or spices. Staff in the Animal Science Department and the PPPI were chosen at random with no notice and asked to sample some bite sized portions of the roast pork and comment whether the flavour, colour, texture and juiciness of the roast pork they consumed was very poor, poor, average, good or excellent. The origin of the cooked pork was not provided to the respondents. Statistical Analysis The experiment was a randomised block design. The treatment effect was assessed with ANOVA in the Systat software (Wilkinson et al., 1992). Bonferroni’s post hoc test was used to separate means only if significant main effects were detected by analysis of variance. The Bonferroni post hoc test is a multiple comparison test based on Student's t statistic and adjusts the observed significance level when multiple comparisons are made. The main factors in the experiment examined were animals, date of sampling, pasture type, zone and interactions.

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RESULTS Committee Involvement The participation by representative on the management committee proved to be successful. Maggie Beer is a member of the SA Primary Industry Research and Development Board and was involved in the development of the SA Food and Fibre Plan. Her skills are in gourmet cooking, managing and owning restaurants and in the promotion of Australian native foods and free-range products. She recommended that a taste test comparing free-range pork and eggs with intensively produced products be undertaken. Peter Jones was also on the committee in his role as a specialist in eco shelter housing for free-range pig and poultry. His specialists input into the committee were in the construction of the eco shelters. These shelters attracted considerable interest on campus and were utilised in student demonstrations. After the shelters were built a local farmer developed a large-scale barn and free-range production systems based on the facilities constructed at Roseworthy campus. In other states the shelters have also been used as housing for free range birds and for rearing of pullets. Meg Parkinson from the VFF is President of the Free-range Egg Producers Association. Her specialist input was on the design of the layer house and management of birds. Christine Ross is involved with a group of free-range pig producers in Victoria. Her specialist input was her knowledge of free-range pig farming and management of the free-range pigs.

Phase 1. Comparison of forage, soil and botanical parameters in a medic pasture before and after grazing by poultry and sheep, and pigs and sheep Phase 1 (year 1) of the experiment involved allowing poultry and sheep and pigs and sheep on medic pasture toward the end of the growing season of the pasture. Comparisons were made on herbage availability, soil characteristics and botanical composition in paddocks as follows;

• Before and after grazing. • Between poultry and sheep paddocks; and between pig and sheep paddocks. • Between different zones in the paddock. Zone 1 was the location in the immediate vicinity of

the animal shelters, zone 2 was some distance from the shelter and zone 3 was the furthermost location from the animal shelters.

Free-range poultry Pasture availability and chemical composition (Tables 26 and 28) There was no difference (P>0.05) between poultry and sheep paddocks or in the zones prior to grazing in the herbage protein content, dry matter and organic matter. At the end of the experiment, the quality of herbage residues in sheep paddocks was poorer, with low crude protein and organic matter content. There was no difference (P>0.05) in pasture quality between zones for both treatments. At the end of the experiment, chicken paddocks had more nutrients available, but the distribution of these nutrients was not different between zones for both sheep and chicken treatments. Botanical composition (Table 27) There was no difference (P>0.05) in the number of snails, medic seed and other seeds between sheep and poultry paddocks before grazing. However, in the sheep paddocks, the un-identified seeds were similar between zones, but there was some variation between zones in the poultry paddock. After 5 months of grazing, there was no difference (P>0.05) in the number of snails between paddocks grazed by sheep and poultry. Paddocks grazed by sheep had fewer (P<0.05) medic pods and other pasture seeds than those foraged by poultry. There was no zone effect for sheep, but the number of pods and other pasture seeds were different between zones in chicken paddocks. There was more pods in zone 2 (1431/m2) than zone 1 (948/m2) and zone 3 (516/m2). Other seed numbers in chicken

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paddocks were reduced from 658/m2 in zone 1 to 125/m2 in zone 3 (P<0.05) while zone 2 had 471 pods /m2. Weed number and insect number (Table 29) After full germination, there was no difference in the number of grass seedlings between sheep and chicken paddocks. There was no wire weed and potato weed in the sheep paddocks, but some were found in the chicken paddocks. There were more unidentified weeds in the sheep paddock than in the chicken paddocks (16 vs. 5/m2). Generally, the sheep paddock had fewer weeds than the chicken paddocks. Very few insects were found in the sheep and chicken paddocks. Soil fertility (Table 30) There was no difference (P>0.05) in soil nitrate-N, ammonia N and pH prior to grazing. At the end of the trial, the sheep paddock tended to have a higher nitrate N. There was no difference in the penetrometer values for sheep and poultry paddocks before and after grazing Production (Table 31) The production performance of layers (Hyline Brown) in the free-range system was compared with the production specifications published by the Hyline company for their brown egg layer strain housed in cages. The free-range birds showed a higher level of mortality (mainly from culling of bullied birds) and lower rates of lay, egg weight and body weight over the period 18-40 weeks. Taste test (Table 32) Overall there was no significant difference (P>0.05) recorded for all respondents in the average scores for flavour, colour and texture. However within the categories of flavour some differences were noted. More people (3 vs. 1) recorded that cage eggs had a ‘very poor’ flavour compared to free-range, while more people (8 vs. 6) indicated that cage egg flavour was ‘good’ compared to free-range eggs. Table 26. Herbage availability in the medic paddocks grazed by poultry and sheep Animal Total air dry biomass

(g/m2) Dry matter

(g/m2) Crude protein

(g/m2) Organic matter

(g/m2) Before grazing

Chicken 585.0 539.9 47.4 493.5 Sheep 502.4 462.9 41.9 423.5 P value 0.190 0.514 0.185 SEM 36.827 5.604 33.087

After grazing Chicken 490.6 417.8 50.4 374.4 Sheep 132.4 109.2 6.3 90.6 P value 0.000 0.017 0.002 0.016 SEM 16.024 66.766 6.105 60.832 Table 27. Botanical composition and snail number in the medic paddock grazed by poultry and sheep

Animal Snail Herbage only Medic pods Others (No./0.1m2) (g/m2) (No./0.1m2) Weight (g/m2) (No./0.1m2) Weight (g/m2)

Prior grazing Chicken 1.21 461.4 123.96 92.2 130.77 31.4 Sheep 0.46 395.1 100.6 81.5 102.58 25.7 P value 0.211 0.162 0.493 0.674 0.406 0.483 SEM 0.3788 29.361 23.1413 17.042 22.3156 5.355

After grazing Chicken 3.8 456.4 965.2 69.5 41.83 8.1 Sheep 1.5 118.1 3.02 2.2 6.19 1.5 P value 0.363 0.017 0.001 0.002 0.020 0.020 SEM 1.647 73.121 11.4554 8.928 8.0443 1.500

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Table 28. Chemical composition (%) of herbage in medic paddocks Animal Dry matter Organic matter Crude protein Chicken 92.3 84.4 8.1 Sheep 92.1 84.3 8.2 P value 0.556 0.856 0.923 SEM 0.186 0.246 0.588 Chicken 91.6 82.1 11.3 Sheep 92.4 76.0 5.6 P value 0.006 0.015 0.000 SEM 0.151 1.272 0.480

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Table 29. Number of weeds (no./0.1m2) in the herbage grazed by sheep and poultry in the medic pasture paddocks Animal Barley

grass Rye grass Other

Grass Total grass

Wire Weed

Caltrop Mustard Potato weed

Medic/ clover

Soursobs Other weeds

Total weeds

Chicken 2.17 7.23 0.19 9.58 2.25 0.04 0.08 0.02 16.54 0.44 0.5 19.88 Sheep 1.27 1.71 0.13 3.10 0 0.04 015 0 3.94 0.98 1.60 6.71

P value 0.214 0.308 0.580 0.249 0.010 1.000 0.414 0.356 0.000 0.227 0.017 0.000 SEM 0.4560 3.5059 0.0756 3.5934 0.4263 0.0241 0.0503 0.0147 0.8228 0.2844 0.2398 1.2205

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Table 30. Soil nitrogen and pH in the medic pasture before and after grazing Animal Nitrate-N

(mg/L) Ammonia_N

(mg/L) pH_water pH_0.01m CaCl

Before grazing Chicken 13.9 4.2 7.4 6.5 Sheep 10.8 5.0 7.0 6.0 P value 0.431 0.393 0.405 0.352 SEM 2.595 0.600 0.298 0.347

After grazing Chicken 18.4 0.0 7.2 6.2 Sheep 24.2 0.1 6.8 5.8 P value 0.203 0.356 0.417 0.506 SEM 2.866 0.088 0.089 0.120 Table 31. Production performance of free-range birds compared to strain standard over 18-40 weeks Treatment Mortality

and Culls (%)

Rate of Lay (%)

(22 weeks)

Rate of Lay (%)

(30 weeks)

Rate of Lay (%)

(40 weeks)

Egg Weight (g)

(40 weeks)

Body Weight (kg)

(40 weeks) Free-range 9.1 72 89 79 57.2 1.93 Standard 1.2 75 94 93 63.9 2.17 Table 32. Response of respondents in taste test comparing cage and free-range eggs for flavour, colour and texture

Treat Flavour

(%) N Colour (%) N Texture

(%) N Free-range very poor 6.25 1 poor 6.25 1 poor 6.25 1 poor 18.75 3 average 31.25 5 average 43.75 7 average 25 4 good 50 8 good 43.75 7 good 37.5 6 excellent 12.5 2 excellent 6.25 1 excellent 12.5 2 Cage very poor 18.75 3 poor 6.25 1 poor 6.25 1 poor 12.5 1 average 25 4 average 37.5 6 average 18.75 3 good 62.5 10 good 50 8 good 50 8 excellent 6.25 1 excellent 6.25 1 excellent 6.25 1 Free-range Ave score 3.3 3.7 3.5 Cage Ave score 3.2 3.7 3.6 P value 0.830 0.908 0.810SEM 0.306 0.191 0.182N=no of respondents in each category

52

Free-range pigs Pasture availability (Table 33). Prior to grazing, barley paddocks had more biomass and nutrient than pasture paddocks, but there was no difference (P>0.05) in nutrients available in the sheep and pig paddocks. A similar results was found after grazing, although pig paddocks had more biomass than those grazed by sheep. Chemical composition (Table 35) There was no difference (P>0.05) in dry matter content, organic matter and crude protein content in herbage grazed by sheep and pigs. Weed number and insect number (Table 34, 36, 37) There was no difference (P>0.05) in number of snails for the treatments during the season, but after grazing pigs paddocks had fewer snails than those grazed by sheep. Pasture paddocks had more weeds and pods than barley paddocks, but no difference was observed between pigs and sheep paddocks prior to grazing. At the end of grazing, paddocks grazed by pigs had more medic pods, other pasture seeds, and barley seeds than paddocks grazed by sheep. In the barley paddocks, there was no difference (P>0.05) in the number of weeds between sheep and pig grazed paddocks. However, in pasture paddocks, there were more barley grass and relatively fewer weeds in pig paddocks in comparison with sheep paddocks. Soil Fertility (Table 38) There was no difference (P>0.05) in soil fertility before grazing. Grazing treatment did not influence soil nitrogen, but soils in pasture paddocks grazed by pigs tended to have higher nitrogen, especially ammonia nitrogen. Soil pH data was not different before and after grazing. Pig Production (Table 39) The daily weight gain of the first batch of pigs ranged from 600 to 800 g, and the back fat was below 14 mm for all carcasses, the maximum thickness recommended for premium pork. In the second batch, growth rate was lower compared with the first batch due to the lower level of supplementary feeding. However, for both batches, the average dressing percentage was over 74%. The pigs grazing the barley crop paddocks had a heavier hot carcass (P<0.05) and tended to be fatter. Preference of respondents to pork from free-range and the intensive system (Table 40) Overall there was no significant difference (P>0.05) recorded for all respondents in their scores for flavour, colour, texture and juiciness of the pork from the different production systems. There was an overall trend for the pork from free-range pigs raised on medic pasture to have better quality attributes than pork from pigs raised in the intensive system or in the free-range on barley pasture. However none of the quality variables approached significance; the closest being juiciness (P=0.21). Within each of the assessments of quality there were some interesting observations. Given more respondents in the taste test some of quality variables may have approached significance. More people (12) said that pork from pigs foraging on medic pasture had ‘good flavour’ compared to 8 people for both the pork from pigs foraging on barley pasture and from the intensive piggery. Likewise 16 people said that the colour of meat from pork of pigs on medic pasture was ‘good’ while 10 people for ‘barley pasture pork’ and 11 people for intensively grown pork said the colour was ‘good’. Seven people noted that the juiciness of the medic pasture pork and intensively grown pork was ‘good’ but only 2 said the juiciness of the ‘barley pasture pork’ was good.

53

Table 33. Herbage availability (g/m2) in the paddocks during the grazing season Paddock Animal Total air dry Dry matter Organic matter Crude

protein Before grazing

Barley Pig 610.1 558.2 518.3 36.6 Barley Sheep 579.2 532.2 485.6 34.1 Pasture Pig 315.3 290.4 261.1 33.0 Pasture Sheep 317.4 291.9 258.5 32.1 Pasture type 0.008 0.008 0.007 0.583 Animal (Pasture) 0.930 0.941 0.887 0.927 SEM 57.047 52.352 46.688 4.647

During grazing

Barley Pig 575.8 503.9 457.9 32.0 Barley Sheep 374.0 335.9 302.4 15.7 Pasture Pig 276.4 256.8 184.1 21.8 Pasture Sheep 152.9 142.8 93.5 9.4 Pasture type 0.031 0.042 0.012 0.256 Animal (Pasture) 0.227 0.270 0.189 0.184 SEM 79.851 74.572 55.747 6.255

After grazing Barley Pig 426.0 369.5 317.9 28.7 Barley Sheep 152.0 132.1 118.9 6.3 Pasture Pig 174.5 139.9 109.9 15.0 Pasture Sheep 15.0 12.4 9.0 1.3 Pasture type 0.006 0.008 0.009 0.016 Animal (Pasture) 0.009 0.014 0.023 0.003 SEM 36.376 35.171 33.188 2.318 Table 34. Snail numbers (no./0.1m2) before, during and after grazing Paddock Animal Before grazing During grazing After grazing Barley Pig 1.08 0.08 0.0 Barley Sheep 1.29 0.0 0.0 Pasture Pig 3.46 0.42 0.0 Pasture Sheep 3.46 1.29 0.25 Pasture type 0.153 0.116 0.374 Animal (Pasture) 0.994 0.399 0.444 SEM 1.2895 0.4067 0.1250 SEM=standard error of means

54

Table 35. Botanical composition of herbage grazed by sheep and pigs

Pasture Animal Pure herbage Pod Other seeds Barley seed (g/m2) No./0.1

m2 Weight (g/m2)

No./0.1 m2

Weight (g/m2)

No./0.1 m2 Weight (g/m2)

Before grazing Barley Pig 365.9 8.75 7.8 2.00 0.9 608.79 235.5 Barley Sheep 380.1 12.63 13.1 3.08 2.3 486.46 183.7 Pasture Pig 212.1 86.46 78.8 214.38 24.3 Pasture Sheep 223.8 79.46 66.6 190.29 27.0 Pasture type 0.020 0.005 0.019 0.001 0.000 - - Animal (Pasture) 0.953 0.913 0.850 0.804 0.649 0.363 0.235 SEM 41.610 13.1091 16.236 25.1155 2.160 73.9449 21.811

After grazing

Barley Pig 400.6 4.25 3.5 1.25 0.4 16.83 5.5 Barley Sheep 142.2 0.29 0.4 0.04 0.0 0.08 0.0 Pasture Pig 150.5 25.13 22.5 0.04 0.0 Pasture Sheep 13.3 6.3 0.5 0.25 0.1 Pasture type 0.008 0.106 0.110 0.076 0.102 - - Animal (Pasture) 0.014 0.064 0.068 0.036 0.054 0.001 0.007 SEM 37.996 5.1022 4.670 0.2104 0.069 0.4167 0.324 SEM=standard error of means

55

Table 36. Chemical composition (% air dry basis) of herbage grazed by sheep and pigs during the season Pasture Animal DM OM CP

Before grazing Barley Pig 91.5 84.9 6.0 Barley Sheep 91.9 83.8 5.8 Pasture Pig 92.0 82.9 10.3 Pasture Sheep 92.0 81.7 10.0 Pasture type 0.026 0.004 0.000 Animal (Pasture) 0.072 0.075 0.654 SEM 0.082 0.347 0.261

During grazing Barley Pig 87.5 79.3 5.6 Barley Sheep 89.7 80.1 4.1 Pasture Pig 92.8 67.9 9.4 Pasture Sheep 93.4 61.5 6.2 Pasture type 0.001 0.003 0.035 Animal (Pasture) 0.086 0.264 0.118 SEM 0.524 2.346 0.925

After grazing Barley Pig 92.2 79.6 7.1 Barley Sheep 93.2 81.2 4.4 Pasture Pig 93.1 71.9 10.1 Pasture Sheep 93.3 67.6 11.1 Pasture type 0.244 0.072 0.002 Animal (Pasture) 0.266 0.765 0.073 SEM 0.354 4.378 0.632 SEM=standard error of means; DM=dry matter; OM=organic matter; CP=crude protein.

56

Table 37. The number of weeds (no/0.1m2) in the paddocks grazed by sheep and pigs during the season Animal Wheat

grass Rye grass Barley

grass Other grass

Total Grass Wire weed

Caltrop Medic clover

Soursobs Other broad leaf

weeds

Total weeds

Barley paddock Pig 0.04 0.92 23.92 0.0 24.88 0.08 1.00 1.50 0.0 0.42 3.00 Sheep 0.0 0.04 4.58 0.08 4.71 0.04 0.92 1.38 0.04 0.42 2.79 Pasture paddock Pig 51.46 0.08 0.04 51.58 0.42 0.4 4.13 1.50 2.67 8.75 Sheep 15.08 0.13 0.13 15.33 0.0 1.50 1.00 3.17 6.00 11.67 Stats Pasture type 0.012 0.462 - 0.621 0.085 0.165 0.731 0.229 0.058 0.134 0.111 Animal (Pasture) 0.069 0.475 0.050 0.605 0.057 0.063 0.243 0.115 0.474 0.575 0.853 SEM 7.6772 0.4612 3.5360 0.0780 8.2010 0.0859 0.5090 0.7933 0.8762 2.0887 3.5880

57

Table 38. Soil fertility in paddocks grazed by pigs and sheep during the season Pasture Animal Nitrate _N

(mg/L) Ammonia _N

(mg/L) pH_water pH_0.01m

Before grazing Barley Pig 11.8 4.0 7.8 7.1 Barley Sheep 8.4 5.1 8.1 7.3 Pasture Pig 15.8 4.6 7.7 6.9 Pasture Sheep 17.0 4.9 7.5 6.6 Pasture type 0.402 0.827 0.488 0.471 Animal (pasture) 0.934 0.717 0.896 0.931 SEM 6.76 0.873 0.528 0.604

After grazing Barley Pig 20.1 0.0 7.1 6.3 Barley Sheep 20.9 0.4 7.0 6.1 Pasture Pig 40.6 6.4 7.6 6.9 Pasture Sheep 30.6 3.0 7.7 7.0 Pasture type 0.039 0.004 0.991 0.898 Animal (pasture) 0.446 0.069 0.265 0.196 SEM 5.006 0.733 0.317 0.342 SEM=standard error of means Table 39. The performance of grazing pigs on barley and medic pasture paddocks in summer Treatment Start weight

(kg) Daily gain

(g/day) Hot carcass weight (kg)

Backfat (mm)

Dressing percentage (%)

Batch 1 Barley crop (n=2) 43.9 751.5 79.2* 11.1 75.6* Pastures (n=2) 44.1 661.3 71.9* 9.9 73.7* SEM. 0.20 18.9 1.12 0.58 0.35

Batch 2 Barley crop (n=2) 47.6 700.2* 65.1* 9.9 76.0 Pastures (n=2) 46.9 533.6* 56.8* 8.4 74.7 SEM. 0.38 17.0 0.99 0.26 0.67 * Values were different between treatments within the batch at P<0.05; SEM=standard error of means

58

Table 40. Taste test comparing free-range pork (flavour, colour, texture and juiciness) and intensively produced pork

Treatment Score Flavour (%) Colour (%) Texture (%) Juiciness (%) Free-range (pasture) Very Poor 0 0 0 5.56 (1) poor 0 0 5.56 (1) 16.67 (3) average 16.67 (3) 5.56 (1) 22.22 (4) 27.78 (5) good 66.67 (12) 88.89 (16) 61.11 (11) 38.89 (7) excellent 16.67 (3) 5.56 (1) 11.11 (2) 11.11 (2) Free-range (barley) Very Poor 0 0 0 11.11 (2) poor 5.56 (1) 0 16.67 (3) 33.33 (6) average 27.78 (5) 38.89 (7) 22.22 (4) 33.33 (6) good 44.44 (8) 55.56 (10) 50.00 (9) 16.67 (2) excellent 22.22 (4) 5.56 (1) 11.11 (2) 5.56 (1) Commercial Undecided 5.56 (1) 5.56 (1) 5.56 (1) 5.56 (1) Very Poor 0 0 0 0 poor 5.56 (1) 0 5.56 (1) 16.67 (3) average 27.78 (5) 22.22 (4) 22.22 (4) 27.78 (5) good 44.44 (8) 61.11 (11) 55.56 (10) 38.89 (7) excellent 16.67 (3) 11.11 (2) 11.11 (2) 11.11 (2) Free-range (pasture) 4.0 4.0 3.8 3.3 Free-range (barley) 3.8 3.7 3.6 2.7 Commercial 3.6 3.7 3.6 3.3 P value 0.395 0.305 0.722 0.210 SEM 0.215 0.175 0.224 0.267

Brackets show number of respondent

59

Phase 2. Comparison of forage, soil and botanical parameters in a wheat stubble before and after grazing by poultry and sheep and pigs and sheep Phase 2 (year 2) of the experiment involved allowing laying hens, pigs and sheep to graze on wheat stubble. Comparisons were made on the following; • herbage availability, soil characteristics and botanical composition before and after grazing in the

respective poultry and sheep paddocks; • direct comparison of the sheep and poultry paddocks and • comparison between the zones within the sheep and poultry paddocks. Free-range poultry Before and after grazing Herbage characteristics, soil nitrate, pH and penetrometer readings in wheat stubble paddock There was no significant (P>0.05) difference in ammonia, pH or penetrometer readings before and after grazing in poultry paddocks. However after grazing, dry matter (DM) was significantly lower (P<0.05) than before grazing, while ash and nitrate levels were higher (Table 41). For the sheep paddocks there was also no significant (P>0.05) difference in dry matter, ash, soil ammonia or pH of the soil before or after grazing. However, there was a significant increase (P<0.05) in penetrometer readings and soil nitrate levels increased (P<0.05) dramatically (Table 42). Table 41. Herbage characteristics; soil nitrate, pH and penetrometer readings for hens before and after grazing on wheat stubble

Treatment Dry matter

(%)

Ash (%) Nitrate (mg/L)

Ammonia (mg/L)

pH (water) pH (CaCl2) Penetrometer

Before grazing

94.91a 16.24a 7.80a 3.51 7.54 6.74 1.44

After grazing

93.63b 23.76b 32.96b 2.25 7.33 6.38 1.87

N 4 4 4 4 4 4 4

P value 0.002 0.013 0.001 0.358 0.751 0.563 0.332

SEM 0.177 1.525 2.768 0.894 0.446 0.410 0.287

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 42. Herbage characteristics; soil nitrate, pH and penetrometer readings for sheep before and after grazing on wheat stubble Treatment Dry matter

(%) Ash (%)

Nitrate (mg/L)

Ammonia (mg/L)

pH (water) pH (CaCl2)

Penetrometer

Before grazing

94.42 17.49 6.69a 5.19 6.68 5.81 1.04a

After grazing

94.13 20.94 39.90b 6.14 6.34 5.48 2.46b

N 4 4 4 4 4 4 4

P value 0.538 0.245 0.000 0.750 0.683 0.665 0.044

SEM 0.311 1.892 3.063 2.015 0.566 0.514 0.396

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

60

Herbage availability, medic and wheat seed numbers and snail numbers in wheat stubble paddock There was no significant difference (P>0.05) in total dry weight, herbage weight, dry matter or organic matter availability in the paddocks before and after grazing by poultry (Table 43). Likewise there was no significant changes in snail numbers, medic pod number and pod weight, wheat and other seed number and seed weight. For the sheep paddocks after grazing there was a significant decline (P<0.05) in total dry weight of herbage, other seed weight, total forage weight, total dry matter weight and organic weight. The reduction in pod weight after grazing approached significance (P=0.053). There was no significant change (P>0.05) in snail numbers, wheat seed numbers and weight before and after grazing (Table 44).

61

Table 43. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by hens Treatment Total dry

wt. (60°C) (g/m2)

Snail no. No/0.1m2

Herbage (only) wt

(g/m2)

Pod no. (No/0.1m2

)

Pod wt (60°C) (g/m2)

Other seed no.

(No/0.1m2

)

Other seed wt (60°C)

(g/m2)

Wheat seeds no. No/0.1m2

Wheat seed wt (g/m2)

Total Forage wt (60°C) (g/m2)

Total DM wt (herbage) (g/m2)

Total OM wt (herbage) (g/m2)

Before grazing

530.1 0 431.0 93.1 5.6 625.8 20.1 0 0 456.7 433.3 359.1

After grazing

473.8 0.08 389.2 215.8 11.2 451.7 10.1 0 0 410.5 384.6 281.6

P value 0.502 0.168 0.490 0.087 0.098 0.542 0.264 0 0 0.483 0.430 0.127 SEM 55.75 0.038 40.22 42.47 2.02 190.74 5.74 0 0 43.71 40.79 30.934 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 44. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by sheep Treatment Total dry

wt. (60°C) (g/m2)

Snail no. (No/0.1m2)

Herbage (only) wt (60°C) (g/m2)

Pod no. (No/0.1m2)


Other seed no.


(g/m2)

Wheat seeds no.

(No/0.1m2)





Before grazing

545.0a 0.03 487.6a 26.1 1.1 414.4 10.6a 0 0 499.3a 471.5a 384.6a

After grazing

302.2b 0.03 235.6b 8.1 0.5 97.5 1.6b 0 0 237.8b 223.6b 173.2b

P value 0.001 1.000 0.002 0.356 0.543 0.053 0.046 0 0 0.001 0.001 0.001 SEM 30.75 0.028 33.42 12.78 0.610 93.37 2.53 0 0 32.87 30.42 25.73 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value in AOV. SEM is standard error of mean

62

Comparison of sheep and chicken paddocks before and after grazing on a wheat stubble paddock Phase 2 of the experiment involved allowing laying hens and sheep to graze on wheat stubble. Comparisons were made on herbage availability, soil characteristics and botanical composition between hen and sheep paddocks before and after grazing. Before and after grazing herbage characteristics, soil nitrate and ammonia in poultry and sheep paddocks There was no significant (P>0.05) difference between hen and sheep paddocks both before and after grazing in dry matter, ash, soil nitrate, ammonia and pH (Table 45). Likewise there was no significant difference in penetrometer reading between the poultry (1.44) and sheep paddocks (1.04) before grazing and after grazing (1.87 poultry vs. 2.47 sheep). Table 45. Dry matter, ash; soil nitrate, ammonia and pH readings for hens and sheep before and after grazing on wheat stubble

Animal

Dry matter (%)

Ash (%)

Nitrate (mg/L)

Ammonia (mg/L)


Before grazing Chicken 94.91 16.23 7.80 3.51 7.54 6.74 Sheep 94.42 17.49 6.69 5.19 6.68 5.81 P value 0.210 0.529 0.486 0.277 0.188 0.196 SEM 0.247 1.325 1.054 0.993 0.410 0.451

After grazing Chicken 93.63 23.76 32.98 2.25 7.33 6.38 Sheep 94.13 20.94 39.90 6.14 6.34 5.48 P value 0.216 0.365 0.266 0.212 0.281 0.230 SEM 0.259 2.037 3.991 1.968 0.592 0.479

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value in AOV. SEM is standard error of mean Herbage availability, medic and wheat seed numbers and snail numbers Before grazing there was no significant difference (P<0.05) between the sheep and chicken paddocks in total dry weight, snail number, herbage weight, pod number, total forage weight, dry matter and organic matter availability in the paddocks before grazing (Table 46). The exception to this was a significant difference (P<0.05) in pod weight between sheep and poultry paddocks. After grazing the chicken paddocks had a significantly higher (P<0.05) number of medic pods, pod weight, other seed numbers and weight, total dry weight and herbage weight. Table 46. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and sheep paddocks before and after grazing on a regenerated medic pasture. Animal Total

dry wt. (60°C)

Snail no.

Herbage (only) wt (60°C)

Pod no.

Pod wt

(60°C)

Other seed no.

Other seed wt

(60°C)

Wheat seeds no.

Wheat seed wt

Total herbage wt (60°C)

Total DM wt (herbage)

Total OM wt (herbage)

Before grazing Chicken 530.1 0 431.0 93.1 5.6a 625.8 20.1 0 0 456.7 433.3 359.1 Sheep 545.0 0.03 487.6 26.1 1.1b 414.4 10.6 0 0 499.3 471.5 384.6 P value 0.748 0.356 0.125 0.108 0.040 0.479 0.313 0 0 0.278 0.302 0.453 SEM 31.35 0.020 22.45 25.07 1.22 197.89 6.12 0 0 25.25 23.87 22.55

After grazing Chicken 473.8 0.08 389.2 215.a 11.2a 451.7a 10.1a 0 0 410.5a 384.6a 281.6 Sheep 302.2 0.03 235.6 8.1b 0.5b 97.5b 1.6b 0 0 237.8b 223.6b 173.2 P value 0.071 0.390 0.061 0.007 0.005 0.017 0.005 0 0 0.045 0.045 0.061 SEM 55.42 0.042 47.23 36.58 1.73 77.07 1.37 0 0 48.51 44.93 33.32 DM, dry matter; OM, organic matter; wt, weight. Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value in AOV. SEM is standard error of mean.

63

Comparison of incidence of weeds in sheep and poultry paddocks after grazing on wheat stubble. After grazing There was a significant (P<0.05) decrease in barley grass and other grasses in the sheep paddocks after grazing compared to poultry. However there was no significant difference between sheep and poultry paddocks after grazing in the incidence of wheat, barley, rye seeds, wild weed seeds, potato, other medic/clover seeds, sour sobs and mustard weed (Table 47). Table 47. Weight of weeds (seeds) in poultry and sheep paddocks after grazing on wheat stubble

Animal Wheat Rye Barley Other grass

Wild weed

Caltrop Potato Medic/ clover

Sour sob

Mustard Other broad leaf weeds

After grazing Chicken 4.28 6.42 0 0.81 2.39a 0 0 5.28 0.94 0 1.31 Sheep 4.06 10.72 0 0.31 0.06b 0 0 2.67 0.61 0 0.42 P value 0.937 0.184 0 0.488 0.001 0 0 0.293 0.752 0 0.182 SEM 1.910 2.026 0 0.479 0.244 0 0 1.604 0.714 0 0.417

Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Comparison of zones in the poultry and sheep paddocks in a wheat stubble paddock Herbage characteristics, soil nitrate, pH, dry matter and ash There was no significant (P>0.05) difference in dry matter, ash (Table 49), nitrate, ammonia, and pH relative to the control in the 3 zones. Likewise after grazing there was no difference in nitrate, ammonia and pH for all the zones including the control. (Table 48). However after grazing there was a significant difference (P<0.05) in the zones for ash with zone 1 being significantly (P<0.05) higher (Table 49) in ash content than zone 2, with zone 3 intermediate. In sheep there was also no significant (P>0.05) difference in nitrate, ammonia or pH of the soil in the 3 zones both before and after grazing (Table 48). However before grazing the ash content in zone 2 before grazing was significantly higher (P<0.05) than zone 1. After grazing however zone 2 was significantly (P<0.05) higher in ash content than zone 3 with zone 1 intermediate (Table 49)

64

Table 48. Nitrate, Ammonia and pH for poultry and sheep in different zones before and after grazing on wheat stubble

Nitrate (mg/L) Ammonia (mg/L) pH (water) pH (CaCI2) Zone Poultry Sheep Poultry Sheep Poultry Sheep Poultry Sheep

Before grazing 1 7.17 8.08 6.09 4.54 7.23 6.50 6.35 5.65 2 8.17 5.17 4.02 7.42 7.40 6.75 6.59 5.88 3 8.05 6.83 0.42 3.61 8.00 6.79 7.27 5.89 Control 6.32 7.20 5.66 3.15 7.57 6.76 6.75 5.82 N 8 8 8 8 12 12 12 12 P value 0.858 0.573 0.052 0.348 0.180 0.840 0.123 0.926 SEM 1.907 1.496 1.565 1.879 0.254 0.253 0.273 0.278

After grazing 1 34.02 39.91 2.58 5.25 7.02 6.11 6.09 5.35 2 35.87 36.67 2.05 6.41 7.14 6.07 6.28 5.17 3 29.03 43.13 2.12 6.76 7.84 6.84 6.78 5.91 Control 34.55 48.29 1.40 2.50 7.53 6.34 6.47 5.51 N 8 8 8 8 12 12 12 12 P value 0.841 0.842 0.825 0.229 0.326 0.569 0.367 0.514 SEM 5.741 10.479 0.999 1.782 0.346 0.452 0.283 0.373

Note: N=12 for Control of nitrate and ammonia, N=11 for control of pH of date 5/6/02 (sheep). Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 49. Variation between zones in dry matter and ash content of wheat stubble before and after grazing by poultry and sheep

Dry matter (%) Ash (%) Zone Poultry Sheep Poultry Sheep

Before grazing 1 94.95 94.15 15.85 13.46a 2 95.02 94.81 16.84 21.57b 3 94.77 94.31 16.02 17.44ab N 8 8 8 8 P value 0.623 0.125 0.879 0.022 SEM 0.187 0.226 1.456 1.890

After grazing 1 93.88 94.03 27.94a 20.27ab 2 93.28 94.50 18.97b 26.24a 3 93.73 93.87 24.37ab 16.30b N 8 8 8 8 P value 0.057 0.250 0.029 0.033 SEM 0.173 0.270 2.198 2.485

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Herbage availability, medic and wheat seed numbers and snail numbers in wheat stubble paddock There was no significant difference (P>0.05) in total dry weight, herbage weight, dry matter or organic matter availability in the different zones both before and after grazing by poultry in the wheat stubble paddock (Table 50). Likewise there were no significant (P>0.05) changes in snail numbers, medic pod number and pod weight, wheat and other seed number and seed weight. For the sheep paddocks there was no significant difference (P>0.05) in total dry weight, herbage weight, dry matter or organic matter availability in the different zones both before and after grazing by sheep in the wheat stubble paddock. In addition there was no significant (P>0.05) changes in snail numbers, medic pod number and pod weight, wheat and other seed number and seed weight (Table 51).

65

Table 50. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in wheat stubble before and after grazing by hens

Poultry Zone Total dry

wt. (60°C) (g/m2)

Snail no. (no/0.1m2)


Pod no. (no/0.1m2)


Other seed No.

(no/0.1m2)


(g/m2)

Wheat seeds no.

(no/0.1m2)


Total Herbage wt (60°C) (g/m2)



Before grazing 1 500.2 0 443.9 95.0 5.7 798.3 31.7 0 0 481.3 456.9 381.2 2 498.1 0 382.8 77.5 4.9 241.7 6.8 0 0 394.4 374.6 308.9 3 592.2 0 466.3 106.7 6.2 837.5 21.9 0 0 494.4 468.5 387.1 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.570 0 (??) 0.658 0.697 0.815 0.134 0.187 1 1 0.568 0.571 0.555 SEM 71.02 0 66.45 24.30 1.38 228.12 9.46 0 0 71.58 67.86 56.25

After grazing 1 603.4 0 469.7 250.8 13.6 503.3 7.8 0 0 491.1 460.8 319.6 2 395.0 0.25 337.3 245.0 12.6 415.0 11.9 0 0 361.8 337.2 267.8 3 423.1 0 360.7 151.7 7.4 436.7 10.6 0 0 378.7 355.7 257.6 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.247 0.160 0.505 0.441 0.199 0.840 0.620 1 1 0.520 0.513 0.706 SEM 93.66 0.104 84.63 60.71 2.54 109.95 2.99 0 0 86.09 80.73 56.05 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt=weight.

66

Table 51. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in wheat stubble before and after grazing by sheep

Sheep Zone Total dry

wt. (60°C) (g/m2)



Pod no. (no/0.1m2)


Other seed No.

(no/0.1m2)


(g/m2)

Wheat seeds no.

(no/0.1m2)


Total Herbage wt (60°C) (g/m2)



Before grazing 1 561.2 0 496.6 31.7 0.9 500.0 13.3 0 0 510.8 480.9 411.6 2 554.8 0.08 510.7 26.7 1.4 386.7 11.9 0 0 524.0 496.7 388.8 3 519.1 0 455.6 20.0 0.9 356.7 6.6 0 0 463.1 436.8 353.5 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.849 0.379 0.729 0.867 0.840 0.713 0.288 1 1 0.682 0.668 0.612 SEM 56.04 0.048 50.637 15.44 0.690 129.25 3.103 0 0 51.48 48.56 41.44 After grazing 1 359.0 0 304.7 14.2 1.1 79.2 1.6 0 0 307.3 289.0 221.5 2 297.0 0 209.1 5.8 0.3 127.5 2.0 0 0 211.3 199.3 145.9 3 250.7 0.08 193.1 4.2 0.3 85.8 1.3 0 0 194.7 182.5 152.2 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.475 0.379 0.341 0.085 0.114 0.579 0.734 1 1 0.340 0.338 0.359 SEM 62.32 0.048 57.19 3.286 0.315 35.16 0.60 0 0 57.63 54.12 40.84 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt= weight.

67

Seed and weed evaluation in different zones of wheat stubble paddock before and after grazing by poultry and sheep. After grazing there was a significant (P<0.05) decrease in wild weeds in the zone closes to the poultry shelter with a gradual increase in wild weeds further away from the shelter (Table 52). There was no significant difference in wheat, rye, barley, other grass, caltrop, medic/clover, sour sob and other broad leaf weeds. After grazing by sheep there was no significant difference (P>0.05) between the zones in the prevalence of weeds.

68

Table 52. Weight of weeds (g/0.1m2) in different zones after grazing by poultry and sheep on wheat stubble paddock

Poultry After grazing

Zone Wheat Rye Barley Other grass Wild weed Caltrop Potato Medics/ clover

Soursob Mustard Other broad leaf

weeds 1 3.50 8.33 0 0.67 1.42b 0 0 4.33 0.83 0 1.58 2 4.75 7.00 0 1.33 2.25ab 0 0 6.67 1.00 0 1.08 3 4.58 3.92 0 0.42 3.50a 0 0 4.83 1.00 0 1.25 Control 0.92 6.08 0 1.75 1.00b 0 0 9.83 2.00 0 0.17 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.681 0.549 0 0.538 0.009 1 1 0.295 0.656 1 0.586 SEM 2.492 2.198 0 0.713 0.526 0 0 2.205 0.725 0 0.751

Sheep After grazing

1 6.08 9.92 0 0.08 0.08 0 0 3.42 0.33 0 0.17 2 4.92 9.83 0 0.67 0 0 0 1.25 0.17 0 0.33 3 1.17 12.42 0 0.17 0.08 0 0 3.33 1.33 0 0.75 Control 1.17 13.08 0 0.67 0.08 0 0 1.25 1.25 0 0 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.290 0.853 1 0.477 0.801 1 1 0.314 0.203 1 0.185 SEM 2.242 3.295 0 0.342 0.072 0 0 1.111 0.479 0 0.248

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

69

Comparison of penetrometer readings between the zones before and after grazing by poultry on the wheat stubble Before grazing in the poultry paddocks there was no difference between the zones in the penetrometer readings. After grazing, however there was a gradual increase in the penetrometer readings furthermost away from the shelter, which is probably indicative of scratching activity of birds, loosening the ground close to the shelter. In the sheep paddocks there was a difference between the zones before grazing but this was not apparent after grazing (Table 53). Table 53. Penetrometer readings in poultry and sheep paddocks before and after grazing on a wheat stubble Poultry Sheep Poultry Sheep Zone Before grazing After grazing 1 1.10 0.56a 2.07a 2.04 2 2.00 0.53a 2.20ab 1.88 3 1.23 2.03b 3.10b 1.69 Control 1.10 0.47a 1.55a 1.63 N 24 24 24 24 P value 0.223 0.000 0.001 0.554 SEM 0.483 0.396 0.339 0.284

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Note: N=12 for control. Production performance of layers while foraging on wheat stubble (18-36 weeks) The Hyline Brown layer pullets were placed in the shelter at 18 weeks and foraged on the wheat stubble until 36 weeks-of-age. At the break of the season in May, birds were relocated from the paddocks to a barn shed to allow the medic pasture to regenerate. Birds remained in the barn for 8 weeks and then were relocated back to the free-range and eco-shelter to forage on the regenerated medic pasture. Egg Production (Fig 2) Compared to the standard production recommended by Hyline, the free-range birds had a delay in reaching point of lay and peak production. When birds were shifted from the shelter to the barn there was a reduction in production (Fig 2). When the birds were returned to the free-range facility there was a gradual improvement in production matching the rate of lay recommended by Hyline. In the last 4 weeks of lay there was a sharp decline in production relative to the standard. Feed intake Birds were fed the recommended feed intake for Hyline birds of 110g/bird/day. Birds were fed half their ration in the morning and the other half in the evening. Egg Weight (Fig 4) The weight of eggs was lower during the early part of lay presumably because birds were consuming less protein than required to achieve the recommended standard. Birds could have been diluting the protein intake by consuming lower protein forage or some of the protein was being diverted to energy requirements as birds tend to be more active in free-range than birds in intensive housing. Body weight (Fig 1) The live weight of free-range layers was compared to the Hyline standard body weight recommended for caged birds. No statistical comparison can be made. However figure indicates that free-range birds had a steady increase in body weight and were approximately 250 g heavier than the standard. When birds were shifted from the free-range to the barn, body weight continued to increase. When birds were given access to the medic pasture again body weight dropped and then stabilised about 200 g above the recommended standard, although weight dropped in the last 4 weeks of lay.

70

Mortality (Fig 3) Mortality of the free-range birds was similar to the standard during the foraging of the wheat stubble. When the birds were shifted to the barn there was an increase in mortality. When the birds shifted back to the free-range mortality declined, but 2 fox attacks in the last 4 weeks of lay resulted in a sharp increase in mortality.

Figure 1. Live weight (kg) for free-range layers versus Hyline standard

0.00

0.50

1.00

1.50

2.00

2.50

24 28 33 38 46 51 55age (week)

wei

ght (

kg)

Free-range chicken'sWeight(kg)

Standard chicken'sweight (kg)

Figure 2. The hen-day production (%)

0.0010.0020.0030.0040.0050.0060.0070.0080.0090.00

100.00

20 24 28 32 36 40 44 48 52 56 60

Age (weeks)

Hen

-day

pro

duct

ion

(%)

Hen-Dayproduction(%)standard Hen-dayproduction (%)

71

Figure 3. Mortality (%) for free-range and standard chickens

0.00

20.00

40.00

60.00

80.00

100.00

20 24 28 32 36 40 44 48 52 56 60

Age (week)

Mor

talit

y (%

)

Mortalities (%)Standard Mortality(%)

Figure 4. The average egg weight for free-range and standard chickens

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

24 28 32 36 45 49 53

Age (week)

Egg

wei

ght (

g)

Free-range eggweight (g/egg)Standard egg weight(g/egg)

72

Grain yield There was no significant difference in yield and digestible energy of the grain from poultry and sheep paddocks, but crude protein of wheat from sheep paddocks was higher than poultry paddocks (Table 54). Crude protein and digestible energy of wheat from zone 1 and zone 2 for both the sheep and poultry paddocks (Table 55) were not significantly different (P>0.05). Table 54. Wheat quality and yield in poultry and pig paddocks

Animal Yield (Tonne/ha) Crude protein (%) Dgestible energy (MJ/kg) for pigsPoultry paddock 1.25 9.1a 14.0 Sheep paddock 1.43 9.8b 14.0 P value 0.500 0.041 NA SEM 0.180 0.20 NA Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. NA=not available Table 55. Wheat quality in zone 1 and 2 of sheep and chicken paddock Zone Poultry Sheep Crude protein (%) Digestibale energy

content for pigs (MJ/kg)

Crude protein (%) Digestible energy content for pigs

(MJ/kg) 1 9.0 14.0 9.9 14.0 2 9.1 14.0 9.7 14.0 P value 0.596 NA 0.640 NA SEM 0.15 NA 0.24 NA

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. NA=not available

73

Free-range pigs

Before and after grazing Herbage characteristics, soil nitrate, pH and penetrometer reading of paddocks where pigs and sheep grazed on wheat stubble There was no significant (P>0.05) difference in dry matter, soil ammonia and pH before and after grazing by pigs. However after grazing, ash, soil nitrate and penetrometer reading were significantly (P<0.05) higher after grazing than before grazing (Table 56). There was no significant (P>0.05) difference in dry matter, ash, and ammonia and soil pH on the wheat stubble paddock before and after grazing by sheep. However after grazing, soil nitrate and the penetrometer reading were significantly (P<0.05) higher in the sheep paddocks after grazing than before grazing (Table 57). Table 56. Herbage characteristics, soil nitrate, pH and penetrometer readings for pigs before and after grazing on wheat stubble Treatment Dry matter

(%) Ash (%)

Nitrate (mg/L)

Ammonia (mg/L)


Penetrometer (Unit?)

Before grazing

93.95 11.69a 16.08a 3.19 7.61 6.89 0.46a

After grazing 94.11 26.72b 45.71b 5.69 7.57 6.86 1.91b N 4 4 4 4 4 4 4 P value 0.469 0.004 0.017 0.311 0.913 0.920 0.001 SEM 0.144 2.363 6.428 1.598 0.197 0.209 0.184 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

Table 57. Herbage characteristics, soil nitrate, pH and penetrometer readings for sheep before and after grazing on wheat stubble in the pig free-range system Treatment Dry matter

(%) Ash (%)

Nitrate (mg/L)

Ammonia (mg/L)


Before grazing

94.31 15.51 12.73a 7.62 7.36 6.62 0.41a

After grazing 94.27 20.86 59.26b 5.15 7.05 6.36 2.53b N 4 4 4 4 4 4 4 P value 0.934 0.174 0.035 0.305 0.623 0.678 0.000 SEM 0.329 2.454 12.114 1.561 0.427 0.431 0.122 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

Herbage availability, medic and wheat seed numbers and snail numbers in pigs and sheep grazing on wheat stubble paddock There was a significant difference (P<0.05) in total dry weight, herbage weight, total herbage weight, total dry matter and organic matter availability in the pig paddocks before and after grazing by pigs (Table 58). There were no significant changes in snail numbers, medic pod number and pod weight, wheat and other seed numbers and seed weight. For sheep there was a significant decline (P<0.05) in total dry weight, herbage weight, total herbage weight, total forage weight, total dry matter weight and organic matter weight. The reduction in other seed numbers and weight after grazing approached significance (P=0.096 and 0.062 respectively). There was no significant change (P>0.05) in snail numbers, medic pod numbers, wheat seed numbers and weight before and after grazing by sheep (Table 59).

74

Table 58. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by pigs on wheat stubble Treatment Total dry

wt. (60°C) (g/m2)


Herbage (only)

wt (60°C) (g/m2)

Pod no. (No/0.1m2)


Other seed no.

(No/0.1m2)

Other seed wt (60°C) (g/m2)

Wheat seeds no.

(No/0.1m2)


Total forage wt (60°C) (g/m2)

Total dry matter wt (herbage) (g/m2)

Total OMwt (herbage) (g/m2)

Before grazing 656.1a 0.14 553.8a 31.1 1.7 981.4 14.1 66.7 2.5 572.0a 537.5a 467.1a After grazing 237.8b 0.03 176.8b 16.9 1.0 51.7 1.4 0 0 179.2b 168.6b 122.4b P value 0.003 0.346 0.002 0.321 0.423 0.158 0.141 0.134 0.136 0.001 0.001 0.001 SEM 62.41 0.077 48.48 9.25 0.57 407.2 5.29 27.34 1.02 47.90 45.31 34.97 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt=weight Table 59. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by pigs on wheat stubble Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt=weight Treatment Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed No

(No/0.1m2)


(g/m2)

Wheat seeds no.

(No/0.1m2)





Before grazing

666.0a 0.17 564.5a 5.3 0.4 382.5 7.5 7.5 0.2 572.7a 540.0a 450.4a

After grazing

295.0b 0.03 234.7b 4.2 0.2 28.1 0.7 0 0 235.6b 222.1b 173.2b

P value 0.003 0.215 0.004 0.807 0.456 0.096 0.062 0.168 0.134 0.003 0.004 0.002 SEM 56.19 0.071 52.04 3.07 0.20 127.24 2.105 3.384 0.091 51.07 48.62 37.92

75

Comparison of pig and sheep foraging in a wheat stubble on herbage, soil and botanical composition There was no significant (P>0.05) difference between pig and sheep paddocks both before and after grazing in dry matter, ash, soil nitrate, ammonia and pH (Table 60). Table 60. Dry matter, ash; soil nitrate, ammonia and pH readings for pigs and sheep before and after grazing on wheat stubble

Dry matter (%)

Ash (%) Nitrate (mg/L)

Ammonia (mg/L)

pH (water) pH (CaCl2) Animal

Before grazing Pig 93.95 11.69 16.08 3.19 7.61 6.89 Sheep 94.31 15.51 12.73 7.62 7.36 6.62 P value 0.378 0.290 0.104 0.570 0.546 0.554 SEM 0.270 2.326 1.641 3.946 0.269 0.297 After grazing Pig 94.11 26.72 45.71 5.69 7.57 6.86 Sheep 92.27 20.86 59.26 5.15 7.05 6.36 P value 0.639 0.147 0.493 0.810 0.373 0.384 SEM 0.237 2.489 13.134 1.515 0.386 0.376

Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Herbage availability, medic and wheat seed numbers and snail numbers Before grazing There was no significant difference (P>0.05) between the sheep and pig paddocks in total dry weight, snail number, herbage weight, pod number, pod weight, seed number and weight, and total forage weight. However, total dry matter and organic matter availability was greater (P<0.05) in the pig paddock than the sheep paddock before grazing commenced (Table 61). After grazing Compared to sheep after grazing, pig paddocks had a significantly higher (P<0.05) total medic pod numbers and weight. There was also no significant difference in insect numbers after grazing between the sheep and pig paddocks (Table 61).

76

Table 61. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and sheep paddocks before and after grazing on a regenerated medic paddock (No./0.1m2) (n=4) Animal Total dry

wt. (60°C) (g/m2)



Pod no. (no/0.1m2)


Other seed no.

(no/0.1m2)


(g/m2)

Wheat seeds no. (no/0.1m2)





Before grazing Pig 656.1 0.14 553.8 31.1 1.7 981.4 14.1 66.7 2.5 572.0 537.5 467.2 Sheep 666.0 0.17 564.5 5.3 0.4 382.5 7.5 7.5 0.2 572.7 540.0 450.4 P value 0.901 0.852 0.894 0.102 0.168 0.359 0.446 0.178 0.170 0.993 0.973 0.760 SEM 53.96 0.10 54.47 9.48 0.589 426.2 5.66 27.44 1.02 52.74 50.41 37.04

After grazing Pig 237.8 0.03 176.8 16.9a 1.0a 51.7 1.4 0 0 179.2 168.6 122.4 Sheep 295.0 0.03 234.7 4.2b 0.2b 28.1 0.7 0 0 235.6 222.1 173.2 P value 0.553 1.000 0.405 0.008 0.005 0.373 0.432 1 1 0.420 0.416 0.355 SEM 64.36 0.028 45.72 2.29 0.14 17.37 0.58 0 0 46.05 43.30 35.90 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt=weight.

77

Comparison of pigs and sheep after grazing a regenerated medic pasture for seeds and weeds After grazing there was no significant (P>0.05) difference between sheep and pig paddocks in the incidence of wheat, barley, rye seeds, other grass, wild weed seeds, other medic/clover seeds, caltrop, sour sobs, mustard weed and other broad leaf weeds (Table 62).

78

Table 62. Numbers of seeds, weed seeds and weeds (no/0.1m2) in poultry and sheep paddocks after grazing on a regenerated medic paddock. Animal Wheat Rye Barley Other grass Wild weed Caltrop Potato Medics/

clover Sour sob


After grazing Pig 9.94 21.56 0 7.17 0.56 0.22 0.08 5.33 5.58 0.03 3.00 Sheep 4.39 15.42 0 1.06 0.19 0.08 0 5.44 8.06 0.11 2.14 P value 0.445 0.391 0 0.102 0.158 0.194 0.168 0.970 0.705 0.356 0.766 SEM 4.809 4.695 0 2.237 0.158 0.067 0.038 1.991 4.405 0.059 1.957 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

79

Comparison of zones for pigs and sheep in a wheat stubble paddock Herbage characteristics, soil nitrate, pH and penetrometer readings There was no significant (P>0.05) difference in dry matter, ash (Table 63), ammonia, and pH relative to the control in the 3 zones before grazing except for soil nitrate, which was significantly higher in zone 2, compared to zone 3. After grazing there was a significant difference in dry matter content in zone two relative to the other zones. Ash was significantly higher (P<0.05) in the 2 zones closest to the pig shelter. There was no difference in soil nitrate, ammonia and pH for all the zones after grazing of the wheat stubble by the pigs (Table 63). In sheep there was also no significant (P>0.05) difference in dry matter, ammonia or pH of the soil in the 3 zones before and after grazing (Table 63). However before grazing the ash content in zone 2 before grazing was significantly lower than zone 3 (P<0.05) with zone 1 intermediate. After grazing however there was no difference in dry matter, ash, ammonia, and pH for any of the zones (Table 63).

80

Table 63. Nitrate, Ammonia and pH in wheat stubble paddocks grazed by pigs and sheep in different zones before and after grazing Dry matter (%) Ash (%) Nitrate (mg/L) Ammonia (mg/L) pH (water) pH (CaCl2) Zone Pig Sheep Pig Sheep Pig Sheep Pig Sheep Pig Sheep Pig Sheep

Before grazing 1 93.93 94.12 12.99 14.07ab 14.67ab 14.20 3.76 5.90 7.67 7.55 6.98 6.84 2 93.73 94.16 10.42 10.98a 27.88b 15.69 2.43 9.66 7.59 7.35 6.87 6.59 3 94.19 94.65 11.66 21.48b 5.70a 8.30 3.37 7.31 7.55 7.20 6.81 6.45 Control NA NA NA NA 12.64ab 8.75 3.71 8.18 7.57 7.44 6.86 6.68 N 8 8 8 8 8 8 8 8 12 12 12 12 P value 0.217 0.419 0.436 0.028 0.022 0.307 0.890 0.718 0.950 0.635 0.912 0.618 SEM 0.182 0.306 1.384 2.612 4.864 3.511 1.397 2.354 0.154 0.196 0.162 0.213

After grazing 1 93.96a 94.29 27.96b 21.18 50.82 47.52 5.19 4.24 7.54 7.03 6.88 6.33 2 94.54b 94.29 34.27b 22.41 56.73 68.66 6.81 4.63 7.37 7.01 6.68 6.33 3 93.82a 94.22 17.94a 19.00 29.58 61.59 5.05 6.58 7.75 7.11 6.95 6.42 Control NA NA NA NA 38.37 36.73 6.03 4.87 7.59 7.22 6.87 6.50 N 8 8 8 8 8 8 8 8 12 12 12 12 P value 0.002 0.972 0.001 0.400 0.186 0.433 0.876 0.689 0.679 0.945 0.835 0.960 SEM 0.130 0.233 2.552 1.769 9.502 16.189 1.726 1.471 0.241 0.270 0.234 0.260 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

81

Herbage availability, medic and wheat seed numbers and snail numbers There was no significant difference (P>0.05) in total dry weight, herbage weight, dry matter or organic matter availability in the different zones both before and after grazing by pigs in the wheat stubble paddock (Table 64). Likewise there was no significant (P>0.05) changes in snail numbers, medic pod number and pod weight, wheat and other seed number and seed weight. This result was also the case for sheep except that there was a gradual increase (P<0.05) in other seed weights from the closet to the furthermost zone. After grazing there was also no difference between the zones in insect numbers for both the sheep and pig paddocks (Table 64).

82

Table 64. Herbage availability, medic, wheat seed numbers and snail numbers for different zones in wheat stubble before and after grazing by pigs and sheep Pig (before grazing)

Zone Total dry wt. (60°C)

(g/m2)



Pod no. (No/0.1m2)


Other seed No.

(No/0.1m2)


(g/m2)

Wheat seeds no.

(No/0.1m2)




Total organic matter wt (herbage) (g/m2)

1 715.2 0 632.0 43.3 2.8 826.7 12.2 41.7 1.2 648.1 608.5 518.3 2 703.8 0.25 534.0 29.2 1.5 1218.3 18.5 59.2 2.6 556.6 521.8 465.1 3 549.3 0.17 495.3 20.8 0.9 899.2 11.5 99.2 3.7 511.4 482.1 418.1 P value 0.227 0.350 0.270 0.550 0.324 0.811 0.642 0.575 0.448 0.305 0.314 0.357 SEM 74.42 0.122 60.32 14.59 0.868 453.57 5.77 39.32 1.38 62.74 58.99 48.66

Pig (after grazing) 1 236.8 0 168.3 18.3 1.1 18.3 0.6 0 0 170.0 159.6 113.0 2 252.1 0 188.1 6.7 0.4 83.3 1.2 0 0 189.7 179.3 119.0 3 224.5 0.08 173.9 25.8 1.6 53.3 2.4 0 0 177.9 166.9 135.1 P value 0.957 0.379 0.952 0.448 0.448 0.227 0.136 1 1 0.956 0.950 0.891 SEM 65.51 0.048 45.88 10.65 0.645 26.11 0.643 0 0 46.43 43.63 33.54

Sheep (before grazing)

1 766.2 0.08 672.0 5.0 0.1 430.0 8.8 0 0 680.9 640.8 545.5

2 539.5 0.25 449.6 0.8 0 195.8 4.3 16.7 0.3 454.2 427.5 376.4 3 692.4 0.17 572.0 10.0 1.2 521.7 9.5 5.8 0.3 583.0 551.8 429.4 P value 0.066 0.672 0.068 0.274 0.060 0.311 0.328 0.417 0.510 0.063 0.063 0.089 SEM 67.35 0.131 65.23 3.95 0.371 152.81 2.66 8.93 0.23 65.57 61.75 53.53

Sheep (after grazing) 1 301.9 0 245.8 5.0 0.3 4.2 0.2a 0 0 246.3 232.2 179.7 2 289.2 0 224.1 5.8 0.2 35.0 0.7ab 0 0 224.9 212.1 163.5 3 293.8 0.08 234.2 1.7 0.1 45.0 1.3b 0 0 235.5 222.0 176.3 P value 0.991 0.379 0.956 0.528 0.308 0.097 0.011 1 1 0.957 0.958 0.950 SEM 67.24 0.048 51.04 2.73 0.12 13.46 0.24 0 0 51.15 48.24 37.53 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt=weight.

83

Seed and weed evaluation of wheat stubble in different zones after grazing by pigs and sheep After grazing there was no significant difference (P>0.05) in the zones in wheat, rye, barley, other grass, caltrop, medic/clover, sour sob, mustard and other broad leaf weeds for both sheep and pigs (Table 65).

84

Table 65. Numbers (no/0.1m2) of seeds, weed seeds and weeds in different zones after grazing by pigs and sheep on the wheat stubble paddock Pigs

After grazing Zone Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic

clover Sour sob


1 4.50 44.83 0 8.42 0.67 0.08 0 2.83 2.92 0 5.58 2 21.17 8.00 0 10.33 0.58 0.33 0.08 5.58 4.17 0.08 2.92 3 4.17 11.83 0 2.75 0.42 0.25 0.17 7.58 9.67 0 0.50 Control 36.58 56.00 0 0.25 0.67 0.25 0 2.92 3.25 0 1.00 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.340 0.476 1 0.267 0.905 0.781 0.538 0.582 0.555 0.402 0.538 SEM 14.461 25.938 0 4.050 0.272 0.175 0.093 2.825 3.761 0.042 2.693

Sheep After grazing

1 3.75 12.67 0 0.67 0.08 0 0 3.17 10.83 0.25 1.50 2 5.00 18.08 0 1.25 0 0 0 12.33 6.33 0.08 4.25 3 4.42 15.50 0 1.25 0.50 0.25 0 0.83 7.00 0 0.67 Control 9.92 14.33 0 0 0 0 0 7.58 10.33 0 0.08 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.649 0.826 1 0.514 0.298 0.402 1 0.407 0.831 0.250 0.529 SEM 3.781 4.166 0 0.676 0.213 0.125 0 5.107 4.230 0.099 2.132 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

85

Production performance of pigs grazing on wheat stubble The daily weight gains and hot carcass weight of the pigs foraging on wheat stubble was significantly higher for the male pigs than the female pigs. The daily gain was equivalent to the batches of pigs raised on barley and medic pastures in year 1 of the trial. The daily weight gain of groups ranged from 573-763 g, back fat 7.5-11 mm and dressing percentage 76%. The average backfat was lower than the maximum backfat of 14 mm recommended by the commercial pig industry for all carcasses. There was a trend for the males to have a fatter carcass (Table 66). Table 66. The performance of pigs grazing on wheat stubble Pig Start weight

(kg) Daily gain


Backfat (mm)

Dressing percentage (%)

Male 28.4 749.4* 81.2* 9.1 75.8 SE 0.80 23.66 2.41 0.69 0.56 Female 26.3 661.3* 73.3* 8.8 76.5 SEM 0.45 23.15 2.14 0.40 0.63 * Values were different between sexes at P<0.05; SEM=standard error of means. Grain yield There was no significant difference in yield, crude protein (CP) and digestible energy (DE) of the wheat from the pig and sheep paddocks (Table 67). There was also no difference in CP and DE of wheat from zone 1 and zone 2 for both the sheep and pig paddocks (Table 68). Table 67. Yield, crude protein (CP) and digestible energy content (DE) of wheat harvested from pig-sheep trial Animal Yield

(Tonne/ha) Crude protein

(%) Digestible energy content for pigs

(MJ/kg) Pig paddock 2.94 11.2 14.0 Sheep paddock 3.07 11.0 14.0 P value 0.930 0.869 0.778 SEM 0.968 0.90 0.03 Table 68. Zone comparison for CP and DE of wheat harvested in the pig and sheep paddocks Pig Sheep Zone Crude protein (%) Digestible energy

content for pigs (MJ/kg)

Crude protein (%) Digestible energy content for pigs

(MJ/kg) 1 11.4 14.0 11.0 14.0 2 11.0 14.0 11.0 14.0 P value 0.713 1 1 1 SEM 0.59 0.04 0.57 0.02

86

Phase 3. Comparison of forage, soil and botanical composition in a regenerated medic pasture paddock before and after grazing by poultry and sheep and pigs and sheep Free-range poultry Herbage characteristics, soil nitrate, pH and penetrometer readings There was no significant (P>0.05) difference after grazing in dry matter, ash, soil ammonia and pH. However after grazing, insect numbers were significantly lower (P<0.05) and penetrometer readings were significantly (P<0.05) higher (Table 69). In sheep there was an increase (P<0.05) in dry matter, ash and penetrometer readings, but a significant decline in soil ammonia, after grazing on regenerated pastures. However, there was no significant difference in pH and insect numbers after grazing by sheep in the poultry free-range system (Table 70). Table 69. Herbage characteristics; soil nitrate, pH, penetrometer readings and insect numbers for hens before and after grazing on regenerated medic pasture. Treatment Dry matter

(%) Ash (%)

Ammonia (mg/L)

Insect (no/0.1m2)


Before grazing

91.06 14.80 4.47 0.50a 7.23 6.41 3.03a

After grazing

92.74 20.15 4.69 0.06b 7.33 6.50 4.82b

N 4 4 4 4 4 4 4 P value 0.070 0.217 0.929 0.025 0.866 0.867 0.007 SEM 0.533 2.740 1.661 0.106 0.398 0.389 0.318 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 70. Herbage characteristics, soil nitrate, pH, penetrometer readings and insect numbers for sheep before and after grazing on regenerated medic pasture. Treatment Dry matter

(%) Ash (%)

Ammonia (mg/L)

Insect numbers (no/0.1m2)


Before grazing

90.81a 14.41b 28.24a 3.31 6.69 5.82 3.90a

After grazing

93.51b 21.16b 1.24b 10.69 7.02 6.10 9.10b

N 4 4 4 4 4 4 4 P value 0.001 0.018 0.001 0.159 0.610 0.674 0.001 SEM 0.288 1.480 2.917 3.244 0.438 0.452 0.392 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Herbage availability, medic and wheat seed numbers and snail numbers After grazing by poultry there was a significant increase (P<0.05) in total dry weight, snail numbers, herbage weight, pod numbers and weight, other seed weight, total forage weight, dry matter and organic matter availability in the regenerated pasture paddocks (Table 71). There were no significant changes in other seed numbers (although it approached significance with P=0.07). In the sheep paddocks after grazing there was a significant increase (P<0.05) in herbage weight, other seed numbers and weight but there was no significant difference in total dry weight, medic pod numbers and pod weight, total forage weight, total dry matter and total organic weight (Table 72).

87

Table 71. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by hens Treatment Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed No.

(No/0.1m2)


Wheat seeds no.

(No/0.1m2)




Total organic matter wt (herbage) (g/m2)

Before grazing

165.8a 0a 137.9a 48.1a 2.3a 12.5 0.4a 0 0 140.6a 128.2a 106.4a

After grazing

526.1b 0.4b 419.0b 811.4b 34.7b 443.6 8.3b 0 0 461.9b 427.9b 334.8b

P value 0.001 0.021 0.001 0.009 0.007 0.078 0.042 1 1 0.001 0.001 0.002 SEM 39.07 0.10 28.27 141.6 5.68 143.6 2.16 0 0 31.37 27.83 31.44 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean; wt=weight.

88

Table 72. Herbage availability, medic and wheat seed numbers and snail numbers for paddocks before and after grazing by sheep Total dry wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed No. (No/0.1m2)


Wheat seeds no. (No/0.1m2)





Total dry wt. (60°C) (g/m2)

Before grazing

128.3 0 99.5a 2.8 0.3 1.4a 0.1a 0 0 99.9 90.8 76.3

After grazing

178.3 0 139.8b 4.7 0.6 80.0b 1.2b 0 0 141.6 132.5 101.0

P value 0.112 0 0.166 0.680 0.458 0.002 0.005 0 0 0.153 0.132 0.199 SEM 18.96 0 18.05 3.17 0.28 10.37 0.18 0 0 18.01 16.93 12.09 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean; wt=weight.

89

Seed and weed evaluation of a regenerated medic pasture before and after grazing by poultry and sheep There was a significant (P<0.05) decrease in number of wheat and rye grass seedlings, wild weeds, other medic/clover species and sour sob after grazing by poultry on regenerated pasture. However there was a significant increase in grass weeds and barley grass after grazing. There was no significant change in potato weed and other broad leaf weeds (Table 73). There was a significant (P<0.05) decrease in number of wheat and rye seeds, sour sob and other broad leaf weeds after grazing by sheep on regenerated pasture. However there was no significant (P>0.05) change in barley grass, other grasses, and wild weeds, other medic clover on the paddock after grazing by sheep (Table 74).

90

Table 73. Numbers of weeds (no/0.1m2) before and after grazing by poultry on a regenerated medic pasture Treatment Wheat Rye Barley Other grass Wild weed Caltrop Potato Medics/

clover Soursob Mustard Other

broad leaf weeds

Before grazing

9.92a 128.69a 0a 0.03a 0.64a 0 0 19.53a 4.81a 0 0.86

After grazing

0.03b 14.89b 2.61b 4.22b 0b 0 0.06 0b 0b 0 0.08

N 4 4 4 4 4 4 4 4 4 4 4 P value 0.031 0.005 0.006 0.002 0.021 1 0.356 0.012 0.017 1 0.249 SEM 2.501 18.749 0.451 0.582 0.145 0 0.039 3.873 1.033 0 0.431 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 74. Numbers of weeds (no/0.1m2) before and after grazing by sheep on a regenerated medic pasture Treatment Wheat Rye barley Other grass Wild weed Caltrop Potato Medic


broad leaf weeds

Before grazing

4.47a 132.56a 0.53 0.06 0.03 0 0 1.97 3.83a 0 1.64a

After grazing

0.03b 4.39b 0.33 0.47 0 0 0 0 0b 0 0b

N 4 4 4 4 4 4 4 4 4 4 4 P value 0.016 0.001 0.747 0.344 0.356 1 1 0.115 0.049 1 0.019 SEM 0.948 9.261 0.406 0.287 0.020 0 0 0.756 1.102 0 0.365 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

91

Comparison of sheep and chicken foraging on a regenerated medic pasture paddock on herbage, soil and botanical composition Before and after grazing -Herbage characteristics, soil nitrate and ammonia in poultry and sheep paddocks There was no significant (P>0.05) difference between hen and sheep paddocks both before grazing and after grazing in dry matter, ash, soil nitrate, ammonia and pH (Table 75). Table 75. Dry matter, ash; soil nitrate, ammonia and pH readings for hens and sheep before and after grazing on wheat stubble Animal

Dry matter (%)

Ash (%)

Nitrate (mg/L)

Ammonia (mg/L)


Before grazing Chicken 91.06 14.80 30.66 4.47 7.23 6.41 Sheep 90.81 14.41 28.24 3.31 6.69 5.82 P value 0.542 0.820 0.667 0.507 0.471 0.412 SEM 0.275 1.137 3.786 1.159 0.498 0.473

After grazing Chicken 92.74 20.15 0.38 4.69 7.33 6.50 Sheep 93.51 21.16 1.24 10.69 7.02 6.10 P value 0.342 0.814 0.168 0.265 0.524 0.462 SEM 0.540 2.900 0.389 3.455 0.321 0.363 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Penetrometer Before grazing on the regenerated medic pasture there was no difference between the poultry and sheep paddocks although the pig and sheep paddocks in the pig free-range system had a lower penetrometer reading (Table 76). After grazing the sheep paddocks in the poultry free-range system had a higher penetrometer reading than the poultry paddocks but in the pig free-range system there was no difference between the pig and sheep paddocks. Table 76. Penetrometer readings before and after grazing by poultry, pigs and sheep on a regenerated medic pasture

Paddocks Before grazing After grazing Poultry 3.03a 4.82a Sheep in poultry system 3.90a 9.10b Pig 0.82b 2.68a Sheep in pig system 1.35b 2.15a P value 0.001 0.001 SEM 0.329 0.262

92

Insect numbers There was no significant difference between chickens and sheep in insect both before and after grazing (Table 77). Table 77. Insect numbers (No./0.1m2) before after grazing by poultry and sheep on regenerated medic pasture

Animal Before grazing After grazing Chicken 0.50 0.06 Sheep 1.08 0.03 P value 0.063 0.537 SEM 0.181 0.030

Herbage availability, medic and wheat seed numbers and snail numbers Before grazing There was a significant difference (P<0.05) between the sheep and chicken paddocks in total dry weight, herbage weight, pod number, pod weight, total forage weight, dry matter and organic matter availability in the paddocks before grazing. The exception to this was the lack of a significant difference (P>0.05) in total dry weight, other seed number and weight (Table 78). After grazing Compared to sheep after grazing, chicken paddocks had a significantly higher (P<0.05) total dry weight, snail number, herbage weight, pod number and pod weight, total forage weight, total dry matter weight and total organic matter weight (Table 78).

93

Table 78. Comparison of herbage availability, medic and wheat seed numbers and snail numbers for hens and sheep paddocks before and after grazing on a regenerated medic pasture. Animal Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed No.

(No/0.1m2)


(g/m2)

Wheat seeds no.

(No/0.1m2)

Wheat seed wt

(g/m2)



Total OM wt (herbage)

Before grazing Poultry 165.8 0 137.8a 48.1a 2.3a 12.5 0.4 0 0 140.6a 128.2a 106.4a Sheep 128.3 0 99.5b 2.8b 0.3b 1.4 0.1 0 0 99.9b 90.8b 76.3b P value 0.117 0 0.026 0.013 0.049 0.124 0.223 1 1 0.025 0.027 0.023 SEM 14.48 0 9.21 9.25 0.57 4.40 0.195 0 0 9.68 9.07 6.98

After grazing Poultry 526.1a 0.44a 419.0a 811.4a 34.7a 443.6 8.3 0 0 462.0a 427.9a 334.8a Sheep 178.3b 0b 139.8b 4.7b 0.6b 80 1.2 0 0 141.6b 132.5b 101.0b P value 0.001 0.021 0.001 0.007 0.005 0.124 0.058 1 1 0.001 0.001 0.002 SEM 40.94 0.10 32.25 141.38 5.65 143.89 2.15 0 0 34.85 31.28 32.95

94

Comparison of seeds and weeds in sheep and poultry paddocks after grazing on a regenerated medic pasture Before grazing Before grazing, poultry paddocks (relative to sheep paddocks) had higher numbers (P<0.05) of wild weed, and medic clover seeds. However there was no difference between sheep and poultry paddocks (P>0.05) in wheat, rye and barley seedlings, grass weeds, including soursob, mustard and other broad leaf weeds (Table 79). After grazing There was a significant (P<0.05) decrease in barley grass and other grasses in the sheep paddocks after grazing compared to poultry. There was no significant difference between sheep and poultry paddocks after grazing in the incidence of wheat, barley and rye grass, wild weed seeds, potato, other medic/clover seeds, sour sobs and mustard weed (Table 79).

95

Table 79. Numbers of weeds and seedlings (no/0.1m2) in poultry and sheep paddocks after grazing on a regenerated medic paddock Animal Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic


broad leaf weeds

Before grazing Chicken 9.92 128.69 0 0.03 0.64a 0 0 19.53a 4.81 0 0.86 Sheep 4.47 132.56 0.53 0.06 0.03b 0 0 1.97b 3.83 0 1.64 P value 0.200 0.899 0.356 0.670 0.025 1 1 0.020 0.665 1 0.365 SEM 2.674 20.677 0.373 0.044 0.146 0 0 3.946 1.510 0 0.562

After grazing Chicken 0.03 14.89 2.61a 4.22a 0 0 0.06 0 0 0 0.08 Sheep 0.03 4.39 0.33b 0.47b 0 0 0 0 0 0 0 P value 1.000 0.055 0.015 0.006 1 1 0.356 1 1 1 0.356 SEM 0.028 3.122 0.478 0.647 0 0 0.039 0 0 0 0.059 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

96

Comparison of zones for herbage characteristics, soil nitrate, pH readings in poultry and sheep paddocks In the poultry paddocks there was no significant (P>0.05) difference in ash, nitrate, ammonia, and pH relative to the control in the 3 zones. Dry matter was significantly higher (P<0.05) in the furthermost zone relative to the closest zone. After grazing was no difference in dry matter, ash, nitrate, ammonia and pH for all the zones including the control (Table 80). In sheep there was also no significant (P>0.05) difference in dry matter, ash nitrate, ammonia or pH of the soil in the 3 zones both before and after grazing (Table 80).

97

Table 80. Dry matter, ash, nitrate, ammonia and pH in soil for poultry and sheep in different zones before and after grazing on regenerated medic pasture. Dry matter (%) Ash (%) Nitrate (mg/L) Ammonia (mg/L) pH (water)

Zone Poultry Sheep Poultry Sheep Poultry Sheep Poultry Sheep Poultry Sheep Before grazing 1 90.63a 91.01 29.52 30.42 2.60 3.03 7.28 6.61 6.48 5.76 2 90.88a 90.77 27.52 20.41 4.81 2.74 6.78 6.67 5.97 5.73 3 91.67b 90.65 34.95 33.90 6.00 4.17 7.63 6.78 6.76 5.95 Control NA NA 31.81 27.86 4.83 4.12 7.04 6.80 6.23 5.90 N 8 8 8 8 8 8 12 12 12 12 P value 0.008 0.470 0.553 0.329 0.371 0.821 0.324 0.971 0.318 0.953 SEM 0.217 0.204 3.810 5.246 1.369 1.399 0.330 0.322 0.309 0.312 After grazing 1 92.76 93.37 0.65 1.12 3.29 8.78 7.15 6.75 6.33 5.83 2 92.70 93.24 0.49 0.42 6.88 3.98 7.10 7.01 6.26 6.04 3 92.71 93.92 NA 2.19 3.90 19.32 7.74 7.31 6.92 6.42 Control NA NA 0.44 0.28 4.58 4.45 7.64 7.05 6.91 6.16 N 8 8 8 8 8 8 12 12 12 12 P value 0.996 0.159 0.611 0.459 0.584 0.448 0.083 0.344 0.086 0.391 SEM 0.485 0.255 0.354 0.972 1.934 7.721 0.212 0.214 0.235 0.243 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean (Note: N=12 for Control of nitrate and ammonia, N=11 for control of pH data for date after grazing).

98

Insect numbers There was no significant difference between chickens and sheep in number insects in the zones before grazing (Table 81). After grazing however, the zone closest to the poultry shelters had a significantly higher number of insects than the other zones, while for sheep there was no significant difference between the zones. Table 81. Insect numbers (no./0.1m2 ) before after grazing by poultry and sheep in the different zones on the regenerated medic pasture Before grazing After grazing Zone poultry sheep poultry sheep 1 0.50 1.92 0.17b 0.08 2 0.67 0.83 0b 0 3 0.33 0.50 0b 0 Control 1.17 1.42 1.17a 0.25 N 12 12 12 12 P value 0.399 0.118 0.001 0.089 SEM 0.359 0.436 0.219 0.077 Herbage availability, medic and wheat seedling numbers and snail numbers in different zones of poultry and sheep paddocks There was no significant difference (P>0.05) in total dry weight, herbage weight, dry matter or organic matter availability in the different zones before grazing by poultry in the regenerated medic pasture (Table 82). Likewise there was no significant (P>0.05) changes in snail numbers, medic pod number and pod weight, wheat and other seedling numbers and seedling weight. After grazing there was a gradual increase (P<0.05) in total dry weight, herbage weight, dry matter and organic matter availability from the closest to the furthermost zones in the poultry paddocks (Table 82). Likewise there was an increase in snail numbers, pod numbers, other seed numbers and weight from the closest to the furthermost zones. There was no significant difference (P>0.05) before and after grazing in the sheep paddocks in total dry weight, herbage weight, dry matter or organic matter availability in the different zones both before and after grazing by sheep in the regenerated medic pastures. Likewise there was no significant (P>0.05) changes in snail numbers, medic pod number and pod weight, wheat and other seedling numbers and seedling weight (Table 82).

99

Table 82. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in a regenerated medic pasture before and after grazing by hens

Poultry Zone Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed No.

(No/0.1m2)


(g/m2)

Wheat seeds no.

(No/0.1m2)

Wheat seed wt

(g/m2)




Before grazing 1 124.3 0 108.3 18.3 0.8 10.0 0.3 0 0 109.4 99.1 84.1 2 164.6 0 150.4 40.0 2.0 16.7 0.5 0 0 152.9 139.1 119.8 3 208.7 0 154.9 85.8 4.0 10.8 0.6 0 0 159.5 146.4 115.3 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.440 1 0.433 0.204 0.136 0.802 0.798 1 1 0.413 0.401 0.427 SEM 46.01 0 27.75 26.66 1.12 7.71 0.287 0 0 28.57 26.24 20.80

After grazing 1 352.7a 0a 302.3a 409.2a 19.9 120.8a 4.0 0 0 326.3a 301.9a 244.9a 2 546.5ab 0a 426.4ab 1235.0b 49.3 184.2a 4.1 0 0 479.8ab 444.1ab 353.7ab 3 679.2b 1.3b 528.3b 790.0ab 34.8 1025.8b 16.8 0 0 579.8b 537.8b 405.9b N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.009 0.003 0.021 0.023 0.055 0.007 0.026 1 1 0.014 0.014 0.032 SEM 70.32 0.30 54.34 200.16 8.25 208.32 3.66 0 0 58.02 53.93 41.96

Sheep Before grazing

1 137.0 0 97.4 3.3 0.2 1.7 0.1 0 0 97.8 89.0 73.9 2 111.3 0 93.3 2.5 0.4 2.5 0.1 0 0 93.8 85.3 72.4 3 136.7 0 107.8 2.5 0.2 0 0 0 0 108.1 98.0 82.7 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.758 1 0.869 0.933 0.901 0.530 0.531 1 1 0.874 0.880 0.879 SEM 27.88 0 19.90 1.82 0.20 1.58 0.08 0 0 20.04 18.30 15.42

After grazing 1 172.6 0 135.0 3.3 0.8 125.8 1.4 0 0 137.3 128.0 97.70 2 146.8 0 132.7 5.8 0.7 28.3 0.7 0 0 134.0 124.9 102.0 3 215.6 0 151.8 5.0 0.3 85.8 1.4 0 0 153.4 144.7 103.2 N 12 12 12 12 12 12 12 12 12 12 12 12 P value 0.422 1 0.829 0.822 0.730 0.190 0.306 1 1 0.830 0.801 0.971 SEM 36.92 0 23.94 2.87 0.53 37.05 0.391 0 0 24.05 22.58 16.99 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

100

Seedling and weed evaluation of regenerated medic pasture in different zones of the paddock after grazing by poultry and sheep In the poultry paddocks before grazing in the control area there were significantly less rye grass, but a higher incidence of other grasses than the other zones (Table 83). All other weed types were not significantly different in the zones. After grazing wheat was higher in the control zone compared to the other zones while rye was lower in the control area compared to the other zones. Barley in the control area was equivalent to all zones. All other weed types were not significantly different between the zones. For sheep before grazing, wheat seedlings were significantly higher in zone 1 than the control but not significantly different from other zones. All other weed types were not significantly different between the zones. After grazing by sheep there was no significant difference (P>0.05) between the zones in the prevalence of weeds (Table 83).

101

Table 83. Numbers of grain seedlings and weeds (no/0.1m2) in different zones after grazing by poultry and sheep on wheat stubble paddock Poultry

Zone Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic Clover

Soursob Mustard Broad leaf weeds

Before grazing 1 9.58 171.50b 0 0b 0 0 0 9.25 7.00 0 1.08 2 8.00 113.50b 0 0.08b 0.67 0 0 24.17 6.92 0 0.83 3 12.17 101.08ab 0 0b 1.25 0 0 25.17 0.50 0 0.67 Control 2.17 26.33a 0 8.08a 0.33 0 0 15.92 7.75 0 0.17 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.111 0.000 1 0.002 0.057 1 1 0.159 0.274 1 0.604 SEM 2.912 21.906 0 1.702 0.324 0 0 5.571 2.923 0 0.490

Before grazing 1 0.08b 17.25b 1.25ab 4.00 0 0 0 0 0 0 0 2 0b 10.92ab 0.92b 3.50 0 0 0 0 0 0 0 3 0b 16.50ab 5.67a 5.17 0 0 0.17 0 0 0 0.08 Control 4.42a 6.83a 2.17ab 6.33 0 0 0 0.08 0 0 0 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.001 0.014 0.028 0.550 1 1 0.402 0.402 1 1 0.538 SEM 0.872 2.479 1.195 1.500 00 0 0.083 0.042 0 0 0.093


1 5.92b 112.25 1.58 0 0 0 0 2.25 4.75 0 1.17 2 4.08ab 132.75 0 0 0 0 0 3.08 0.83 0 1.08 3 3.42ab 152.67 0 0.17 0.08 0 0 0.58 5.92 0 2.67 Control 0.08a 88.83 0.08 3.67 0 0 0 2.92 9.08 0.08 0.83 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.005 0.306 0.418 0.049 0.402 1 1 0.267 0.266 0.402 0.256 SEM 1.099 24.583 0.793 1.073 0.042 0 0 0.978 2.919 0.042 0.703

After grazing 1 0 3.25 0.50 0.08 0 0 0 0 0 0 0 2 0 5.42 0.08 0.75 0 0 0 0 0 0 0 3 0.08 4.50 0.42 0.58 0 0 0 0 0 0 0 Control 0.25 8.58 2.50 0.83 0 0 0 0 0 0 0 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.089 0.454 0.084 0.519 1 1 1 1 1 1 1 SEM 0.077 2.414 0.715 0.384 0 0 0 0 0 0 0 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

102

Penetrometer Before and after grazing on the regenerated medic pasture there was no difference in the zones of the poultry paddocks and the control area (Table 83). Before grazing there was a difference between the control area and zone 3, but not zone 1 and 2. After grazing in the sheep paddock there was no difference between the zones and the control area (Table 84). Table 84. Penetrometer reading before and after grazing by poultry and sheep on a regenerated medic pasture

Poultry Sheep Zone Before grazing After grazing Before grazing After grazing 1 3.50 4.18 3.34ab 8.72 2 2.74 5.53 3.60ab 9.13 3 2.85 4.75 4.75b 9.45 Control 2.90 3.46 2.01a 9.13 N 24 24 24 24 P value 0.415 0.074 0.002 0.195 SEM 0.486 0.689 0.577 0.334

Note: N=12 for control; SEM, standard error of means. Values with different letters were significantly different between zones.

103

Comparison of pigs and sheep foraging on a regenerated medic pasture paddock on herbage, soil and botanical composition Before and after grazing Herbage characteristics, soil nitrate, pH and penetrometer readings There was no significant (P>0.05) difference after grazing in dry matter, ash, nitrate and soil pH in the pig paddocks (Table 85). However after grazing, penetrometer readings were higher almost approaching significance (P=0.058). There was no significant (P>0.05) difference after grazing in dry matter, ash, ammonia, and soil pH and penetrometer readings for sheep grazing paddocks in the pig free system. However after grazing, soil nitrate was significantly (P<0.05) lower after grazing in the sheep paddocks (Table 86). Table 85. Herbage characteristics, soil nitrate, pH and penetrometer readings for pigs before and after grazing on regenerated medic pasture Treatment DM (%) Ash

(%) Nitrate (mg/L)

Ammonia (mg/L)

pH (water)

pH (CaCl2)

Penetrometer

Before grazing

91.03 15.64 34.52 1.67 7.47 6.72 0.82

After grazing

91.98 16.02 21.70 2.46 7.40 6.57 2.68

N 4 4 4 4 4 4 4 P value 0.186 0.903 0.149 0.494 0.708 0.531 0.058 SEM 0.448 2.084 5.482 0.771 0.133 0.158 0.561 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 86. Herbage characteristics, soil nitrate, pH and penetrometer readings for sheep before and after grazing on regenerated medic pasture Treatment DM(%) Ash (%) Nitrate

(mg/L) Ammonia

(mg/L) pH (water) pH (CaCl2) Penetrometer

Before grazing

91.59 16.84 32.21a 1.35 7.05 6.19 1.35

After grazing

92.36 18.51 12.35b 2.55 7.32 6.39 2.15

N 4 4 4 4 4 4 4 P value 0.242 0.478 0.000 0.123 0.480 0.621 0.340 SEM 0.418 1.561 1.814 0.474 0.252 0.266 0.547 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Herbage availability, medic and wheat seed numbers and snail numbers for pigs and sheep grazing in pig free-range system There was a significant increase (P<0.05) in total dry weight, snail numbers, herbage weight, other seed weight, total forage weight, dry matter and organic matter availability in the paddocks after grazing by pigs on regenerated pasture (Table 87). There were no significant changes in medic pod numbers, other seed number, wheat seed number and wheat seed weight. There was no significant (P>0.05) difference in total dry weight, snail numbers, pod numbers and weight, other seed numbers and weight, total herbage, dry matter and organic matter availability in the paddocks after grazing by sheep on regenerated pasture (Table 88).

104

Table 87. Herbage availability, medic and wheat seedling numbers for regenerated medic paddock before and after grazing by pigs Treatment Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed no. (No/0.1m2)


Wheat seeds no.

(No/0.1m2)





Before grazing

189.4a 0a 184.6a 0 0 0 0a 0 0 184.6a 167.8a 137.8a

After grazing

418.9b 0.11b 363.6b 80.6 4.1 701.9 10.1b 7.5 0.3 378.1b 347.6b 290.3b

P value 0.001 0.050 0.013 0.096 0.105 0.097 0.029 0.202 0.207 0.009 0.008 0.021 SEM 26.69 0.032 36.35 28.89 1.50 253.0 2.51 3.70 0.167 36.37 32.99 34.55 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Wt= weight. Table 88. Herbage availability, medic and wheat seedling numbers for regenerated medic paddock before and after grazing by sheep Treatment Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed no.

(No/0.1m2)


(g/m2)

Wheat seeds no.

(No/0.1m2)





Before grazing

143.2 0 137.8 0 0 0 0 0 0 137.8 126.1 102.4

After grazing

208.8 0.19 152.9 5.3 0.3 333.1 2.9 0 0 156.1 144.2 114.3

P value 0.143 0.356 0.501 0.220 0.108 0.173 0.156 1 1 0.404 0.359 0.420 SEM 27.56 0.137 14.88 2.73 0.10 152.49 1.27 0 0 14.39 12.91 9.73 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

105

Grain seedlings and weed evaluation of a regenerated medic pasture before and after grazing by pigs and sheep There was a significant (P<0.05) decrease in number of rye and barley seedlings and broad leaf weeds after pigs had grazed the regenerated medic pasture. However, there was no change in wheat seedlings, other grass seedlings, wild weeds, potato, medic/clover, sour sob and mustard weeds. There no significant difference in wheat, rye, barley seedlings, grass weeds, medic/clover pods and sour sob in paddocks grazed by sheep in the pig free-range system. However there was a significant reduction in other broad leaf weeds. The reduction in wheat, rye and barley grass approached significance (Table 89).

106

Table 89. Numbers of grain seedlings and weeds (no/0.1m2) before and after grazing by pigs on a regenerated medic pasture Treatment Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic

clover Soursob Mustard Other broad

leaf weeds Before grazing

1.81 34.19a 50.36a 0.28 0.42 0 0 1.50 19.94 0.14 1.06a

After grazing

0.94 2.89b 2.03b 2.44 0 0 0.03 0 0 0 0.06b

N 4 4 4 4 4 4 4 4 4 4 4 P value 0.332 0.000 0.080 0.148 0.147 1 0.356 0.141 0.129 0.356 0.034 SEM 0.577 1.703 16.263 0.923 0.177 0 0.020 0.626 8.014 0.098 0.259 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Table 90. Numbers of grain seedlings, weed seeds and weeds (no/0.1m2) before and after grazing by sheep on a regenerated medic pasture in the pig free-range system Treatment Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic

clover Soursob Mustard Other broad


3.11 27.75 16.61 0.36 0 0 0 2.56 13.72 0.17 3.39a

After grazing

0 0.08 0.58 0.25 0 0 0 0 0 0 0.08b

N 4 4 4 4 4 4 4 4 4 4 4 P value 0.057 0.056 0.081 0.800 1 1 1 0.110 0.141 0.356 0.000 SEM 0.933 8.268 5.401 0.297 0 0 0 0.965 5.725 0.118 0.338 Means within columns followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

107

Comparison of pig and sheep foraging in a regenerated medic pastures on herbage, soil and botanical composition Herbage characteristics, soil nitrate and ammonia in pig and sheep paddocks before and after grazing There was no significant (P>0.05) difference between pig and sheep paddocks both before grazing and after grazing in dry matter, ash, soil nitrate, ammonia and pH (Table 91). There was a trend after grazing however for soil nitrate level to be higher (P=0.10) in the pig paddock compared to the sheep paddock. Table 91. Dry matter, ash content of wheat stubble and soil nitrate, ammonia and pH readings for pigs and sheep before and after grazing Animal DM (%) Ash

(%) Nitrate (mg/L)

Ammonia (mg/L)


Before grazing Pig 91.03 15.64 34.52 1.67 7.47 6.72 Sheep 91.59 16.84 32.21 1.35 7.05 6.19 P value 0.526 0.232 0.735 0.755 0.239 0.154 SEM 0.590 0.640 4.617 0.694 0.227 0.227

After grazing Pig 91.98 16.02 21.70 2.46 7.40 6.57 Sheep 92.36 18.51 12.35 2.55 7.32 6.39 P value 0.152 0.510 0.105 0.918 0.763 0.566 SEM 0.165 2.524 3.468 0.580 0.173 0.210 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Insect numbers There was no significant difference between poultry and sheep in number of insects in the zones before and after grazing (Table 92). After grazing however, the zone closest to the poultry shelters had a significantly higher number of insects than the other zones, while for sheep there was no significant difference between the zones Table 92. Insect numbers (No./0.1m2) before after grazing by pigs and sheep on the regenerated medic pasture Animal Before grazing After grazing Pig 0.64 0.22 Sheep 0.56 0.08 P value 0.824 0.303 SEM 0.253 0.087

P is the probability value from the analysis of variance; SEM is the standard error of the mean. Herbage availability, medic and wheat seed numbers and snail numbers Before grazing There was no significant difference (P>0.05) between the sheep and pig paddocks in total dry weight, snail number, herbage weight, pod number, pod weight, seed number and weight, and total forage weight. However, total dry matter and organic matter availability was greater (P<0.05) in the pig paddock than the sheep paddock before grazing commenced (Table 93). After grazing Compared to sheep after grazing, pig paddocks had a significantly higher (P<0.05) total dry weight, herbage weight, forage weight, total dry matter weight and organic matter availability (Table 93).

108

Table 93. Comparison of herbage availability, medic and wheat seedling numbers for pigs and sheep paddocks before and after grazing on a regenerated medic paddock

Animal Total dry wt. (60°C)

(g/m2)



Pod no. (No/0.1m2)


Other seed no.

(No/0.1m2)


Wheat seeds no.

(No/0.1m2)





Before grazing Pig 189.4 0 184.6 0 0 0 0 0 0 184.6 167.8a 137.8a Sheep 143.2 0 137.8 0 0 0 0 0 0 137.8 126.1b 102.4b P value 0.058 1 0.053 1 1 1 1 1 1 0.053 0.046 0.041 SEM 13.98 0 13.79 0 0 0 0 0 0 13.79 11.78 9.66

After grazing Pig 418.9a 0.1 363.6a 80.6 4.1 701.9 10.1 7.5 0.3 378.1a 347.6a 290.3a Sheep 208.8b 0.2 152.9b 5.3 0.3 333.1 2.9 0 0 156.1b 144.2b 114.3b P value 0.006 0.691 0.007 0.116 0.126 0.411 0.119 0.202 0.207 0.005 0.005 0.011 SEM 35.73 0.14 36.78 29.02 1.51 295.43 2.81 3.70 0.17 36.60 33.41 34.57

Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

109

Comparison of pigs and sheep after grazing a regenerated medic pasture for weeds Before grazing Prior to grazing there was no significant (P>0.05) difference in incidence of wheat, rye and barley grass, other grasses, wild weeds, medic/clover grass, soursob and mustard seeds. The exception to this was the significant (P<0.05) lower level of other broad leaf weeds in the pig paddock compared to the sheep paddock (Table 94). After grazing After grazing there was no significant (P>0.05) difference between sheep and pig paddocks after grazing in the incidence of wheat, barley and rye grass, other grass, wild weed seeds, other medic/clover seeds, caltrop, sour sobs, mustard weed and other broad leaf weeds (Table 94).

110

Table 94. Numbers of grain seedlings and weeds in poultry and sheep paddocks after grazing on a regenerated medic paddock Animal Wheat Rye barley Other grass Wild weed Caltrop Potato Medic/

Clover Soursob Mustard Other broad


Pig 1.81 34.19 50.36 0.28 0.42 0 0 1.50 19.94 0.14 1.06a Sheep 3.11 27.75 16.61 0.36 0 0 0 2.56 13.72 0.17 3.39b P value 0.409 0.606 0.213 0.849 0.147 1 1 0.540 0.671 0.902 0.008 SEM 1.041 8.384 17.123 0.295 0.177 0 0 1.150 9.848 0.153 0.424

After grazing Pig 0.94 2.89 2.03 2.44 0 0 0.03 0 0 0 0.06 Sheep 0 0.08 0.58 0.25 0 0 0 0 0 0 0.08 P value 0.103 0.090 0.177 0.144 1 1 0.356 1 1 1 0.537 SEM 0.348 0.983 0.668 0.924 0 0 0.020 0 0 0 0.030 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

111

Comparison of forage, soil and botanical composition in different zones in a regenerated medic pasture before and after grazing by pigs and sheep Herbage characteristics, soil nitrate, pH and penetrometer readings There was no significant (P>0.05) difference in dry matter, ammonia, and pH relative to the control in the 3 zones before grazing except for soil nitrate which was significantly higher in zone 2, compared to zones 1and 3 and ash which was also higher in zone 2 compared to other zones. After grazing there was a significant difference in ash, nitrate, ammonia and pH between the zones but dry matter content in zone two relative to the other zones was significantly (P<0.05) higher (Table 95). In sheep there was no significant (P>0.05) difference in dry matter, ash, nitrate, ammonia or pH of the soil in the 3 zones before and after grazing (Table 95).

112

Table 95. Nitrate, ammonia and pH in regenerated wheat stubble paddocks grazed by pigs and sheep in different zones before and after grazing Dry matter

(%) Ash (%) Nitrate

(mg/L) Ammonia

(mg/L) pH (water) pH (CaCl2)

Zone Pig Sheep Pig Sheep Pig Sheep Pig Sheep Pig Sheep Pig Sheep Before grazing

1 91.28 91.23 14.01a 16.59 36.63ab 24.00 1.57 0.13 7.53 7.31 6.83 6.42 2 91.30 91.70 18.76b 16.66 48.70b 33.93 1.53 2.32 7.46 6.99 6.70 6.11 3 90.51 91.85 14.15a 17.28 18.23a 38.69 1.90 1.59 7.43 6.86 6.62 6.04 Control 28.46ab 32.38 2.76 1.63 7.43 7.07 6.62 6.21 N 8 8 8 8 8 8 8 8 12 12 12 12 P value 0.622 0.527 0.009 0.822 0.037 0.266 0.598 0.129 0.978 0.383 0.832 0.496 SEM 0.647 0.398 1.110 0.857 7.300 5.206 0.817 0.648 0.185 0.188 0.183 0.182

After grazing 1 91.66a 92.38 14.10 18.47 22.15 10.23 4.02 1.57 7.42 7.46 6.64 6.51 2 92.14b 92.43 18.41 18.94 28.54 14.59 1.60 2.18 7.38 7.26 6.52 6.32 3 92.13ab 92.26 15.54 18.13 14.40 12.23 1.77 3.90 7.39 7.24 6.55 6.33 Control NA NA NA NA 23.00 22.03 2.73 10.26 7.40 7.32 6.56 6.42 N 8 8 8 8 8 8 8 8 12 12 12 12 P value 0.023 0.730 0.363 0.950 0.522 0.655 0.097 0.552 0.998 0.784 0.951 0.864 SEM 0.128 0.152 2.125 1.777 6.663 7.946 0.734 5.405 0.152 0.167 0.150 0.179 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean.

113

Insect numbers There was no significant difference in number of insects (no/0.1 m2) in the zones for pigs both before and after grazing. However the number of insects before grazing in zones 1 and 2 in the sheep paddocks were significantly lower than the control area but after grazing there was no difference between the zones or the control area (Table 96). Table 96. Insect numbers (no./0.1m2) in the zones and control area of paddocks grazed by pigs and sheep on the regenerated medic pasture Zone Before grazing After grazing

Pig Sheep Pig Sheep 1 0.17 0.50a 0.33 0.08 2 1.17 0.25a 0.17 0.08 3 0.58 0.92ab 0.17 0.08 Control 1.67 1.67b 0.08 0.08 N 12 12 12 12 P value 0.151 0.006 0.587 1.000 SEM 0.482 0.285 0.130 0.083 Means within columns within a grazing period followed by a different letter are significantly different (P<0.05). P is the probability value from the analysis of variance. SEM is the standard error of the mean. Penetrometer Before grazing, zone 1 in the pig paddock had a significantly lower penetrometer reading than zone 3 with the control area and zone 2 intermediate. After the grazing the pig paddocks had a gradual increase in the penetrometer readings from zone 1 to zone 3. In the sheep paddocks there was no significant difference in the penetrometer reading both before and after grazing (Table 97). Table 97. Penetrometer readings in the zones and control area of paddocks grazed by pigs and sheep on the regenerated medic pasture Pigs Sheep Zone Before grazing After grazing Before grazing After grazing 1 0.58b 2.15a 1.28 2.59 2 0.76ab 2.36a 1.33 1.60 3 1.12a 3.54b 1.43 2.25 Control 0.93ab 1.94a 1.41 1.55 N 24 24 24 24 P value 0.002 0.023 0.843 0.106 SEM 0.140 0.522 0.183 0.460

Note: N=12 for control; SEM, standard error of means, Values with different letter are significantly different between zones. Herbage availability, medic and wheat seed numbers and snail numbers There was no significant difference (P>0.05) in total dry weight, snail number, herbage weight, pod number and weight, other seed numbers and weight, dry matter or organic matter availability in the different zones both before and after grazing by pigs in the regenerated medic pasture paddock. After grazing total dry weight, herbage weight, total forage weight and organic matter availability was significantly higher (P<0.05) in zone 2 than zone 3 but equivalent to zone 1 (Table 98). For sheep there was no significant difference both before and after grazing between the zones in herbage availability, seed numbers and snail numbers (Table 98).

114

Table 98. Herbage availability, medic and wheat seed numbers and snail numbers for different zones in regenerated medic pasture before and after grazing pig Zone Total dry

wt. (60°C) (g/m2)



Pod no. (No/0.1m2)


Other seed no.

(No/0.1m2)


Wheat seeds no.

(No/0.1m2)





Before grazing 1 138.7 0 134.9 0 0 0 0 0 0 134.9 123.0 104.2 2 269.9 0 263.4 0 0 0 0 0 0 263.4 239.7 190.2 3 159.8 0 155.5 0 0 0 0 0 0 155.5 140.9 119.1 P value 0.003 1 0.003 1 1 1 1 1 1 0.003 0.003 0.009 SEM 26.53 0 26.55 0 0 0 0 0 0 26.55 23.98 19.75

After grazing 1 389.5a 0 329.3ab 14.2 0.8 950.0 12.5 0 0 342.5ab 313.9ab 265.4ab 2 581.8b 0.17 511.0b 86.7 4.4 917.5 11.2 7.5 0.3 526.9b 485.2b 394.6b 3 285.5a 0.17 250.6a 140.8 7.0 238.3 6.8 15.0 0.7 265.0a 243.6a 210.9a P value 0.002 0.345 0.003 0.320 0.385 0.147 0.521 0.282 0.260 0.004 0.004 0.018 SEM 53.51 0.092 51.18 58.49 3.170 282.0 3.69 6.54 0.28 52.47 48.08 44.18

sheep Before grazing

1 108.7 0 105.1 0 0 0 0 0 0 105.1 95.7 78.3 2 161.4 0 155.3 0 0 0 0 0 0 155.3 141.9 115.5 3 159.5 0 153.1 0 0 0 0 0 0 153.1 140.6 113.3 P value 0.163 1 0.177 1 1 1 1 1 1 0.177 0.167 0.160 SEM 21.62 0 20.99 0 0 0 0 0 0 20.99 19.11 15.03

After grazing 1 213.0 0 158.4 11.7 0.4 151.7 1.6 0 0 160.4 148.3 118.5 2 238.3 0.50 171.1 1.7 0.2 640.0 5.1 0 0 176.3 162.9 130.9 3 175.3 0.08 129.1 2.5 0.3 207.5 2.1 0 0 131.4 121.5 93.5 P value 0.677 0.317 0.692 0.307 0.611 0.288 0.346 1 1 0.668 0.671 0.576 SEM 50.46 0.246 35.28 5.02 0.18 234.92 1.81 0 0 35.62 33.01 25.42

115

Weed evaluation of regenerated medic pasture in different zones after grazing by pigs and sheep Before and after grazing there was no significant difference (P>0.05) between the zones in wheat, rye, barley, other grass, caltrop, medic/clover grasses, sour sob, mustard and other broad leaf weeds for both sheep and pigs. However rye grass was significantly lower in the sheep paddock than the control zone (Table 99).

116

Table 99. Numbers of grain seedlings and weeds in different zones after grazing by poultry and sheep on regenerated medic pasture Pig

Zone Wheat Rye Barley Other grass Wild weed Caltrop Potato Medic clover

Soursob Mustard Other broad leaf weeds

Before grazing 1 3.00 53.67 46.67 0 0.17 0 0 1.58 24.33 0 0.67 2 0.67 23.92 97.17 0 0.67 0 0 0.67 12.92 0.42 0.67 3 1.75 25.00 7.25 0.83 0.42 0 0 2.25 22.58 0 1.83 Control 1.83 16.67 47.75 0 0.17 0 0 1.58 18.33 0.33 0.42 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.525 0.043 0.096 0.218 0.382 1 1 0.736 0.843 0.499 0.427 SEM 1.096 9.492 24.546 0.336 0.234 0 0 0.997 9.699 0.245 0.654

After grazing 1 0.42 0.83 1.58 3.83 0 0 0.08 0 0 0 0.08 2 1.58 3.42 3.17 2.08 0 0 0 0 0 0 0 3 0.83 4.42 1.33 1.42 0 0 0 0 0 0 0.08 Control 8.83 3.42 3.75 8.67 0 0 0 0 0 0 0.08 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.035 0.222 0.409 0.074 1 1 0.402 1 1 1 0.801 SEM 2.248 1.242 1.193 2.080 0 0 0.042 0 0 0 0.072


1 1.67 18.75 15.67 0.08 0 0 0 2.50 12.58 0 1.75 2 7.67 23.75 26.92 1.00 0 0 0 4.58 9.75 0.33 6.15 3 0 40.75 7.25 0 0 0 0 0.58 18.83 0.17 2.00 Control 0 37.83 8.83 0 0 0 0 0.58 11.33 0.08 1.67 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.174 0.543 0.216 0.427 1 1 1 0.454 0.730 0.647 0.072 SEM 2.767 12.552 7.196 0.502 0 0 0 2.023 6.038 0.191 1.463

After grazing 1 0 0.17a 0.33 0.25 0 0 0 0 0 0 0.08 2 0 0.08a 0.25 0.25 0 0 0 0 0 0 0.08 3 0 0a 1.17 0.25 0 0 0 0 0 0 0.08 Control 0.17 1.17b 2.17 4.25 0 0 0 0 0 0 0 N 12 12 12 12 12 12 12 12 12 12 12 P value 0.101 0.000 0.133 0.081 1 1 1 1 1 1 0.801 SEM 0.056 0.196 0.637 1.293 0 0 0 0 0 0 0.072

117

Production performance of pigs grazing on regenerated medic pasture The daily gain of pigs grazing on the regenerated medic pasture averaged 450 g/day for male pigs and 518 g/day for female pigs (Table 100). This result was lower than daily gain achieved in the previous growth trials. Pigs were supplemented with about 50% of the daily recommendation and obtained the remainder of their nutritional requirements from the forage available in the paddock. The lower daily gain of these pigs was reflected in their lower backfat levels. No difference could be detected between male and females in their production performance. Table 100. Daily gain, carcass weight, backfat and dressing percentage of pigs foraging on regenerated medic pasture Pig Start weight

(kg) Daily gain


Backfat (mm) Dressing percentage (%)

Male 31.5 457.6 60.2 7.1 72.4 SE 0.46 12.45 1.11 0.06 0.79 Female 32.7 518.1 65.9 10.7 72.1 SE 0.42 23.30 2.20 0.44 0.75 SE=standard error. Pig Behaviour The distribution of pigs in different areas of the paddock was monitored during the day. Pigs spent the majority of their time under the trees (40%), followed by the shelter (23%) and zone 1 (23%) of the paddock (Fig 5).

Fig 5. Pig's location during the day and % of time in each location

05

1015202530354045

Shelte

rDun

gRac

eFee

dTree

s

Zone 1

Zone 2

Zone 3

Place

Perc

enta

ge o

f act

ivity

(%)

Activity (%)

118

DISCUSSION Phase 1 (year 1)- Integration of poultry into a medic pasture during the late growing season of the pasture. Production aspects During the summer of 2000/2001, South Australia experienced its hottest summer in a century. The maximum temperature recorded in the shelter was 470C. Overall, there were 17 days when the temperature exceeded 370C in the shelter. The shelter was sited on a small hill in the paddock and there was always a breeze that ventilated the birds in the shelter. During the hot weather hens remained within the shelter or within the immediate surrounds and were able to keep cool by dust bathing in the litter or in the soil, where water had been sprayed. The reduction in performance of birds relative to the benchmark was expected considering the heat wave conditions experienced and the reduction in the natural daylight hours after the summer solstice. However, the production performance by free-range birds in this study is similar to the data reported by Barnett (1999) on the experience with free-range egg production in Europe. Birds were very active in the paddock during overcast conditions and also when light drizzly rain was falling. It was apparent that birds were attracted to the insects, which were more active during this period. Birds foraged mainly within 30-40 m of the shelter but would also forage further out into the paddock especially when attendants were present. As the birds moved further out into the paddock they tended to leave clumps of pasture. Level of floor laying was less than 1% of egg production, but dirty (20%) and broken eggs were initially a problem, which was overcome by collecting eggs twice daily. Birds favoured nest boxes lowest to the ground. Egg weight and body weights were lower than the benchmark but this was expected given that birds were very active in the free-range environment. There were a number of birds low on the pecking order, which were bullied by other birds. In most cases these birds had to be culled from the flock. Birds were contained in the shelter overnight and there were no bird losses from foxes, despite a large population of foxes in the region. Comparisons of flavour, texture and colour of eggs Overall there was no difference recorded by the taste test panel for flavour, colour and texture of eggs from free-range and cage eggs. However within the categories of flavour some points are worth noting. More people (3 vs. 1) stated that cage eggs had a very poor flavour compared to free-range. On the other hand more people (8 vs. 6) suggested that cage egg flavour was good compared to free-range. The evidence from this very small in house taste test panel suggests that respondents cannot distinguish eggs from a caged bird and a free-range bird. However this taste test was conducted with free-range birds feeding on late season medic pasture. Other pasture types may have imparted more flavour to the eggs. Agronomic aspects The Merino wethers used in the trail were stocked at a rate of 6 per paddock giving almost twice the stocking rate of poultry when assessed on a kg/ha basis. The effect of having a higher stocking density in the sheep paddocks was shown in the herbage availability data with almost 3 times the amount of biomass, dry matter and organic matter still available in the poultry paddocks after 3 months of foraging. Sheep grazed the medic pods heavily leaving fewer pods than poultry. The paddocks foraged by the free-range birds did not need to be sown with medic for the next season given the high abundance of seeds.

119

Snails are a huge problem in Southern Australia and cause considerable damage to crops. The snail population at the time of sampling was low probably as a result of the dry weather conditions. Likewise very few insects were also observed at the time of sampling. Sheep, however, were very effective in grazing wire weed, which contaminated the paddocks whereas poultry avoided this weed. In contrast, the number of unidentified weeds in the sheep paddock was greater than the poultry paddock. This raises the possibility that sheep and poultry could be grazed together in some circumstances, to provide a method for reducing weeds, using sheep to graze weeds they prefer and poultry to consume weed seeds that sheep avoid. Soil fertility was not different between the sheep and pig paddocks.

Wheat Cropping Grain yields did not differ between the sheep and poultry paddocks although the sheep paddocks produced a higher crude protein in the weight presumably because of the higher levels of nitrogen in the soil. Given the low stocking density of both the sheep and poultry in the paddocks this result may differ in other production systems where both sheep and poultry are generally stocked at higher rates. Phase 2 (year 2)- Integration of poultry into wheat stubble. Production aspects It was not possible in this study to make a statistical comparison of the production performance of free-range birds versus a control group of birds in cages. Instead the production standards of the Hyline strain recommended for caged birds were used as the basis for the comparison. The free-range birds were heavier than the standard. Birds were observed ranging extensively in the paddocks and probably consumed considerable quantities of spilt grain from the wheat harvest, probably resulting in their higher body weight. When birds were shifted from the free-range to short term residence in the barn, the body weight continued to increase.

Egg Production Compared to the standard production recommended by Hyline, the free-range birds had a slight delay in reaching point of lay and peak production presumably because they were exposed to a decreasing light pattern. Birds were not provided artificial light in the shelter. Consequently birds did not receive the day length required to maximise production. When birds were shifted from the shelter to the barn there was a reduction in production. This was not unexpected because birds had to adapt to a new environment, and the birds could not forage feed sources from the paddock.

Mortality Mortality of the free-range birds was similar to the standard while foraging on the wheat stubble. Birds roamed widely in the paddock and there was little evidence of feather pecking. When the birds were shifted to the barn there was an increase in mortality probably as a result of the birds being forced to cope with a new environment at a higher stocking density.

Egg Weight. The weight of eggs was lower during the early part of lay presumably because the birds were consuming less protein than required to achieve the recommended standard. Birds could have been diluting the protein intake by consuming lower protein forage or some of the protein was being diverted to energy requirements as birds are generally more active than cage birds when given access to free-range facilities. Agronomic aspects After sheep had grazed the wheat paddocks there was an increase in the penetrometer readings in the paddocks. This reflects the trampling effect that sheep have on forage and soil with continued grazing

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whereas poultry paddocks showed no change in penetrometer readings. Birds scratch the soil and loosen it ensuring the surface soil does not get hard. There was no difference between the zones in penetrometer readings for poultry. The sheep zones were different before grazing in penetrometer readings but after grazing they were similar. This reflects the nature of sheep, which is to forage on most areas of the paddock. There was no effect of grazing on soil pH with this low stocking density of both sheep and poultry but soil nitrate levels were higher after grazing suggesting that animal droppings were contributing to the increase. Poultry had no major effect in the wheat stubble paddocks on forage availability at the end of the grazing season, whereas sheep had an about a 50% reduction in organic matter. Sheep will consume the stubble whereas poultry tend to pick up small portions of the stubble. Wheat stalks are high in fibre and are not readily consumed by poultry. When direct comparisons were made of sheep and chicken paddocks no difference could be observed in soil fertility, pH before and after grazing although sheep tended to have a higher level of soil ammonia and pH. The poultry did not consume the same amount of medic pods and other seeds in the paddocks compared to sheep. Medic pods are probably difficult for the bird to consume whereas sheep would favour the pods and seeds as an alternative to wheat stubble. This resulted in the sheep paddocks (after grazing) having lower levels of herbage weight than before grazing. Sheep are commonly used to graze out weeds and in the wheat stubble after grazing there was a lower weight of wild weeds in the paddocks compared to before grazing although there was no difference with weight of other weeds before and after grazing. The weight of wild weeds after grazing by poultry on sheep stubble closest to the shelter were less than further out whereas in the sheep paddocks the weight of wild weeds did not vary between the zones. This once again suggests that poultry foraged in the zones closest to the shelter where as sheep moved throughout the paddock. When an examination was made of the zones in each of the poultry and sheep paddocks there was no difference in soil fertility, pH and nitrates. For poultry paddocks there was no variation between the zones in dry matter content. In the sheep paddocks however there was some variation in dry matter content between the zones. Phase 3- Integration of poultry into a regenerated medic pasture.

Production aspects When birds were given access to the medic pasture body weight dropped and then stabilised at 200 g above the recommended standard; although body weight fell in the last 4 weeks of lay probably due to two fox attacks.

Egg Production When the birds were returned to the free-range facility onto the medic pasture there was a gradual improvement in production matching the rate of lay recommended by Hyline. Two fox attacks in the last 4 weeks of lay while birds were foraging during the day resulted in a sharp decline in production relative to the standard performance expected of these birds when housed in cages. Mortality When the birds were shifted back to the free-range to graze the medic pasture mortality declined, but 2 fox attacks in the last 4 weeks of lay resulted in a sharp increase in mortality. A large number of the birds appeared to die as a result of severe stress of being chased by the fox, rather than being injured. Foxes At the Roseworthy Campus, foxes are a common problem with shooting and baiting restricted because of the proximity of paddocks to housing and campus facilities. Throughout the project the policy of locking birds in the shelter at night proved effective in averting the fox problem. However 2 daylight attacks were made on the birds. The perimeter fencing was constructed to keep sheep from straying but was not of sufficient height to stop foxes.

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Egg Weight. The egg weight of birds while foraging on medic pasture was equivalent to the standard recommended by Hyline. Agronomic Aspects In the poultry paddocks, dry matter and soil fertility did not change during the growing season for the regenerated medic pasture. However penetrometer readings increased in the poultry paddocks as the soil dried out toward the end of the growing season of the pasture. This was also observed in the sheep paddocks where the increase in surface hardness was more apparent. There was a reduction in insect numbers before and after grazing in the poultry paddocks indicated by a related student study examining the crop contents of birds foraging in the paddock. Insects consumed by the birds were observed in the crop together with seeds, grass, soil and small stones. Inn the sheep paddocks there was an increase in insect numbers. This provides evidence for a species difference in selection of food resources. In the sheep paddocks there was a dramatic increase in the dry matter content in the paddock after grazing, although soil ammonia was lower after grazing. This may have been due to a sampling problem, as there were a number of bare areas in the paddock, which by chance were randomly selected. The stocking density of poultry was low and they could not keep pace with the increase in forage availability, including medic pods and other seeds during the growing period of the pasture. In the sheep paddocks the forage availability was the same before and after grazing. The exception to this was the availability of other seeds, which increased in number and weight during the growing season in the sheep paddocks. Poultry appeared to have a preference for wheat, rye grass, other wild weeds, other clover species and sour sob. However there was an increase in the amount of barley grass in the poultry paddocks. In the sheep paddocks there was a decline in all grasses and weeds. It is apparent that poultry have a preference for some weeds and grasses whereas sheep forage on all weeds. On the other hand competition by various grasses and weeds with the medic pasture for nutrients and light during the growing season may have contributed to the differences observed. Poultry did not consume as much forage as sheep, which probably altered the dynamics of competition between the grass species for growth in the paddock. In addition, variation between plant species in growth during the season may have also contributed to this finding. When comparing soil fertility of sheep and poultry paddocks both before and after grazing there was no difference. Penetrometer reading of the soil surface was higher in the poultry free-range system before grazing than the pig free-range system. The soil was sandier in the pig free-range system contributing to the lower penetrometer readings. After the grazing period on the regenerated medic pasture the penetrometer readings was higher in the sheep paddocks in the poultry free-range system. This was probably due to the continuous trampling of the soil and forage by sheep in these paddocks. Herbage availability was greater in the poultry paddocks than the sheep before grazing but after grazing the differences in poultry herbage availability was greater. This also applied to medic pods and pod weight. The major difference between the sheep and chicken paddocks in weeds and other grasses were in the number of medic clover grasses. After grazing, the sheep paddocks had a lower number of barley grasses and other grasses than poultry paddocks. There was no difference between the zones in soil fertility and pH for both the sheep and poultry paddocks. The only exception was the higher dry matter content in the zone furthermost from the shelter. There was no difference in the sheep and chicken paddocks in the number of insects although after grazing the number of insects in all the zones was lower than the control zone. This shows that poultry have the ability to reduce insects by consuming them or acting as a deterrent for insects to habituate an area. Herbage availability and medic pod number and weight in the zones did no differ before grazing but after grazing there was an increase in medic pod number, snail numbers, dry matter and organic matter availability. This indicated that poultry mainly foraged in the zones closest to the shelter. Researchers are attempting to increase the ranging ability of poultry in free-range systems as discussed in the literature review. In contrast the sheep paddocks showed no difference between the zones in

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forage availability, medic pod numbers and other seeds. This indicates that sheep range widely over the paddocks compared to poultry. Before grazing, rye grass seedling numbers were higher in all the poultry zones compared to the control zone and this difference was maintained after grazing. This suggests that ryegrass flourishes in poultry paddocks. On the other hand after grazing wheat grass was higher in the control paddock compared to all other zones in the poultry paddocks indicating a preference by poultry to consume wheat grass. In the sheep paddocks however there was no difference in grass numbers in the zones, reinforcing the grazing differences between sheep and poultry. Conclusions The main objective of this project was to demonstrate a free-range pig and poultry production system, which integrated with a traditional crop/pasture rotation system. This objective was achieved. Both pigs and poultry obtained feed resources from the paddocks and production performance of both pigs and poultry approached industry standards. The disappointing aspect was the fox attacks on poultry. The birds were locked up at night and this avoided any attacks except for the last month of the production trial. It is recommended in free-range systems that fences of sufficient height and strength be built to prevent foxes entering. This was not possible in this trial but in any future trials adequate protection for poultry is required. The fox attacks occurred during the day, which was not expected. In the pig trial electric fencing was used to keep pigs in their paddocks. This worked well, except for the first week of the trial with pigs tending to approach the fence and bolt through the fence when they received a light shock on their nose. As the pigs approached market age the mating activities in the pigs increased and on occasions this prevented some pigs obtaining their fair share of feed. The shelters constructed were ideal for both pigs and poultry. Even under extreme weather conditions the shelters provided adequate protection from the element for the birds. The only concern was the very strong winds, which caused the blinds to flap loudly and driving rains, which sometimes entered the shelter. Both pigs and poultry were able to utilise the forage sources in the paddocks and grazed weeds. The stocking density used in the trial was very low. Use of larger number of birds and or pigs on pasture heavily infested with weeds offers an alternative approach to controlling weeds and avoiding the use of chemicals. The use of strip grazing to clean up weeds and moving the animals frequently to new areas is a strategy which could be employed particularly on farms where organic grain is being produced. The use of sheep with other species to selectively graze weeds and grasses has potential. The advantage of the low stocking density is that the production system is environmentally sustainable. Tradition free-range systems can cause environmental problems especially where land has been denuded and animals continually utilise the same area of land for extended periods. The use of animals in a cropping pasture system has considerable potential and the system established at Roseworthy attracted considerable interest. Most people were pleased to see the animals utilise the free-range facility and their perception was that it was a good system of production albeit with some of the problems that resulted many years ago in the commercial industry moving to intensive systems of production.

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PUBLICATIONS Y. J. Ru, P. C. Glatz and H. Reimers (2001). Performance of grazing pigs in southern Australia. Pig

Industry News June 2001 P. 5. Glatz, P.C.. Y.J. Ru, H Reimers, M.Fischer, S Wyatt and B. Rodda (2002). Integrating free-range

poultry into a pasture and cropping rotation. Pig and Poultry Fair 2002, Seminar Notes and Research Summaries; in press.

Ru, Y.J. Glatz, P.C. H Reimers, M.Fischer, S Wyatt and B. Rodda (2002). Performance of grazing

pigs in southern Australia. Pig and Poultry Fair 2002, Seminar Notes and Research Summaries; in press.

Ru, Y.J., Glatz, P.C.. H Reimers, M.Fischer, S Wyatt and B. Rodda (2002). Grazing pigs and sheep

have similar influence on soils. Pig and Poultry Fair 2002, Seminar Notes and Research Summaries; in press.

Glatz, P.C. and Ru, Y.J. (2001). Eco shelter housing of free-range poultry integrated into a

pasture/crop rotation in the wheat belt of Australia. Proceedings of the 6th European Symposium on Poultry Welfare, pp. 299-301

Ru, Y.J., P. C. Glatz, H. Reimers, M. Fischer and S. Wyatt (2001). Performance of grazing pigs in

summer in southern Australia. In Manipulating Pig Production VIII p. 44

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