Final Project Webinar 22nd of April 2021

Free-ranging profiles of commercial and heritage

meat-purpose chickens, their welfare and gastrointestinal tract

features

Joanna Marchewka et al.

Organic meat purpose chicken production

• Increased public concerns of animal welfare and sustainability in conventional poultry production systems

• Consumers’ interest in meat from poultry reared in low-input systems:

• housing and management aim for optimizing health and welfare of chickens

• In EU organic system birds are provided with ranging areas

Final Project Webinar 22nd of April 2021

Organic meat purpose chickens in Poland

• Poland - the largest EU-27 chicken producer (20% of EU chicken production)

• Poland covers only 0.3% of the EU organic food market value; (6 EURO/year/person spent on organic products in 2020)

• Between 6th and 9th rank in number of certified organic farms in EU (all species) but only 4% of livestock production in Poland is organic

• Organic poultry production marginal in Poland (less than 1% of the total poultry production); Western Europe - above 10%

Gornowicz et al., 2017

FreeBirds: Optimizing the use of the free range as the key to improve organic chicken production

Project aims: • Relation between chickens’ free range use and bird

health, welfare and performance • Smart tools and management strategies

Study aims in Poland 2

stra

ins

of c

hick

ens Focus

Animal welfare

Gastrointestinal tract morphometrics, small intestine

microstructure, amount of pasture and feed ingested

Weather conditions

Range use

Material and methods

Experiment: • Summer 2018

• SASSO C44 and Green-legged Partridge

• 12 pens with outdoor runs • 10 birds/pen

• Data collected from wk. 5 (birds can go outdoors) to wk. 10

• 24/7 video recordings

• birds tagged with a laminated color tag

SASSO and Green-legged Partridge • Sasso is a slow-growing broiler hybrid

• GLP is a dual purpose heritage Polish breed – widely accepted in practice (high quality of meat and eggs)

• Both are well adjusted to outdoor conditions

• Different exterior (colored chicken vs. wild type coloration)

• Not comparable in body weight, size and growth rates

Ranging profiles • Not all broiler chickens in a flock access the outdoor

range when the opportunity is provided

• Campbell et al. (2016) profiled individual laying hens, differing in their ranging profiles

• Profiling attempt has not been performed in meat-purpose chickens

We ranked the birds based on their range use frequency and distributed into 3 ranging profiles:

• outdoor-preferring ranging profile

• moderate-outdoor ranging profile

• indor-preferring ranging profile

Investigation levels

Production system

Genetic strain/breed/hybrid

Flock

Ranging profile

Individual

Call focus: organic and low input systems

SASSO C44 and Green-legged Partridge

Experimental design: pens

Outdoor-preferring Moderate-outdoor Indor-preferring

120 birds in 12 pens

Focus: Animal welfare • Despite consumers’ belief that access to an outdoor range

improves chicken welfare, still little is known if it is true

Genetic strain/breed/hybrid

• Improvements in breast plumage cover, gait scores, cardiovascular function and reduction in weight (i.e. Ross 308)

• Outdoor range use association with the welfare condition in slower-growing broiler chicken genetic strains may vary

Ranging profile

Ranging profiles in hens were strongly associated to coping styles (Campbell et al., 2016)

Coping styles are related to the levels of stress and disease vulnerability (Koolhaas and Van Reenen, 2016)

Welfare condition of birds presenting different ranging profile may vary

•

•

•

Welfare Assessment Scale 0 (optimal condition) to 2 (major deviation from optimal condition): • plumage condition • comb pecking wounds • skin injuries • dirtiness • toe damage • eye pathologies • footpad dermatitis • hock burns

Either 1 (present) or 0 (absent): • respiratory infections • diarrhea

Scale 0 (perfect walking) and 5 (unable to walk) - Welfare Quality gait scoring method

• walking ability

Results: Animal welfare

• Effect of interaction between genetic strain and ranging profile on respiratory infections

• Sasso condition was worse for FPD, plumage condition, comb pecking wounds, dirtiness, and toe damage

• Toe damages were more frequent in indoor-preferring birds, as compared to other ranging profiles

Implications: Animal welfare

• To implement strategies encouraging chickens to use the outdoor area, evidence is needed that outdoor-preferring birds present better or equal welfare as indoor-preferring and moderate-outgoing birds

• Associations between ranging profiles and welfare of investigated genetic strains identified

• Further research to establish the causal relationship between range use and indicators of birds’ welfare needed

Focus: Animal welfare

Focus: Gastrointestinal tract morphometrics, small intestine microstructure, amount of pasture and feed ingested

• Optimal gastrointestinal tract development is important for nutrient absorption and for poultry to resist diseases and assure welfare

• Birds reared with access to the pasture consume material found outdoors

• Is frequency of the outdoor range use associated with the ingested material and the development of birds gut?

Gastrointestinal tract measurements

• The aim of the current study was to investigate:

gastrointestinal small intestine amount of pasture-tract microstructure originating material

morphometrics and feed

• Birds divided into 3 ranging profiles

• Analysis separately for the Sasso and Green-legged Partridge

Results: Gastrointestinal tract morphometrics, small intestine microstructure, amount of pasture and feed ingested

• Villi in terms of their height and area were the lowest for indoor-preferring Sasso, as compared to outdoor-preferring ones

• In the crops of the moderate-indoor Green-legged Partridges there was significantly more pasture matter, as compared to other ranging profiled birds of that breed

• Correlations between the gastrointestinal tract and its content measurements were different for each breed

Implications: Gastrointestinal tract measurements

• The optimal gut development is important for the efficiency of the nutrient absorption and the ability of poultry to resist disease

• The level of the development of the gastrointestinal tract and its content may be considered as potential retrospective indicators of the birds ranging profile

• Links between intestinal microflora vs. gastrointestinal tract measurements vs. behaviour and emotional states still need to be explored

Focus: Weather conditions • Outdoor environmental conditions influence animal

comfort

• Comfort zone related to weather parameters for free-range broilers not investigated yet

Ranging areas: • Long, open spaces with

little shelter

• Shelter, if present, often unavailable to all birds in a flock at once (Stadig et al., 2017)

Focus: Weather conditions

• Outdoor shelters often not protective from all weather parameters

• Single-type shelters don’t fulfil protective role to all birds within the flock, if individuals are sensitive to varying weather conditions

Weather conditions

• Previous studies averaged the breed or treatment group range use

• Weather data collected each minute throughout the whole experiment by an automatic weather station

• Exact matching of an individual bird range access with instantly changing weather parameters

Results: Weather conditions • Associations between weather parameters and range use for 30%

of Green-legged Partridge and Sasso chickens

• Weather explained up to 35% of the range use variability

• Between breeds, range use associations with different weather parameters were identified:

• Negative associations with relative humidity most frequently in Green-legged Partridges

• Positive associations with atmospheric pressure most common in Sasso chickens

• Ranging areas design to accommodate individual preferences/needs, e.g. by including provision of multiple construction and vegetation elements

Conclusions

• Dividing birds into ranging profiles helped to describe associations between their range use and health and welfare more precisely than only by comparing genetic strains

• Evidences found that outdoor-preferring birds present better welfare as indoor-preferring and moderate-outgoing birds

• Indoor-preferring birds require further characterisations

• Gastrointestinal tract health and function parameters were associated to range use frequency

• Birds presented various individual range use reactions under the same weather conditions

• Individualized range use optimization strategies may be required for best production outcomes

Final Project Webinar 22nd of April 2021

Thank you for attention