INDUSTRIAL TRAINING REPORT

ON

TITLE OF TRAINING

COMPLETED AT

NAME OF THE COMPANY /FIRM

By

NAME OF STUDENT

INDEX NO.

Aquatic Resources Technology Degree Programme

Faculty of Animal Science and Export Agriculture

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Uva Wellassa University

2014

TITLE OF TRAINING

AT

NAME OF THE INDUSTRY

By

NAME OF THE STUDENT

INDEX NO

This report is submitted in partial fulfillment of the requirement of the degree ofBachelor of Science in Aquatic Resources Technology

of

Faculty of Animal Science and Export AgricultureUvaWellassa University of Sri Lanka

2012/2013

Approved by

Mrs. R.G.M. RajapaksheInternal SupervisorAquatic Resources Technology Degree ProgrammeUva Wellassa UniversityBadullaSri Lanka

Date:.

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.Dr. (Mrs) S.C. JayamanneHeadDepartment of Animal ScienceUvaWellassa UniversityBadullaSri Lanka

Date:..

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Abstract

Shrimp farm extension and monitoring unit in Batticaloa was selected as a placement toconduct the industrial training during the fourth year second semester. Shrimp farming isa developing industry in Sri Lanka. Knowing a thorough knowledge about shrimpindustry is important to develop this industry.

Although this is a two months of training session I received lot of experience as well asexposure in shrimp farming and shrimp hatchery. This training program helped to Gainedknowledge about shrimp farm extension and monitoring. This report includes, briefintroduction about the shrimp industry, hatchery, shrimp farming and shrimp biology.

So, through this training program I got massive and valuable opportunity to exposeshrimp farming and hatchery management. As well as we gather big experience to ourlives.

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Acknowledgement

This note of acknowledgement is to convey my heartiest gratitude and appreciation to allthose who helped me in numerous ways to complete this training.First, I extend my deepest gratitude to my Deparment of Animal Science, Uva WellassaUniversity for organizing this training program.

My deepest thanks goes to my external supervisor Mr.S.Ravikmar, district AquaculturistShrimp farming monitoring and extention unit, National Aquaculture DevelopmentAuthority of Sri Lanka Puttukudirippu, who had given me his continues support andencouragement with essential guidance and suggestions to make my training a greatsuccess.

I extend my deepest gratitude to my internal supervisor Dr. S.C. Jayamanne, Dean of thefaculty of Animal Science Department of Animal Science for her valuable assistance,encouragement and guidance.

I profusely thank to our training coordinator Mrs. I. U. Wickramaratne, lecturer,Department of Animal Science, Uva Wellassa University, for giving this valuableopportunity of industrial training in the fulfillment of my B.Sc. Aquatic Resources andTechnology degree program.

I would also like to extend my thanks to the respective staffs of NAQDA who gave theirvaluable support to complete my industrial training session successfully.

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Symbols and Abbreviations

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List of Tables

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List of Figures

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List of Plates

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Chapter 1

1 Introduction

A shrimp farm is an aquaculture business for the cultivation of marine shrimp or prawnsfor human consumption. Commercial shrimp farming began in the 1970s, and productiongrew steeply, particularly to match the market demands of the United States, Japan andWestern Europe. The total global production of farmed shrimp reached more than 1.6million tons in 2003, representing a value of nearly 9 billion U.S. dollars. About 75% offarmed shrimp is produced in Asia, in particular in China and Thailand. The other 25% isproduced mainly in Latin America, where Brazil, Ecuador, and Mexico are the largestproducers. The largest exporting nation is Thailand (FAO, 2009).Farmed shrimp export accounts for approximately 50% of the total export earnings fromSri Lankan fisheries. It was their second most valuable export fisheries in 2007,generating Rs.2487 millions (approx. 25 million USD). More than 90% of the harvestedcultured shrimp are exported, going mostly to Japan followed by United States ofAmerica and countries of European Union. The black tiger shrimp, Penaus monodon isthe main species cultured. The majority of grow out shrimp farms in Sri Lanka followssemi intensive culture practice. Farmed shrimp production was 2,220mt in 2008compared to 9,240mt from wild capture. Aquaculture production peaked in 1998 at 6,520mt. The shrimp industry was responsible for 40,000 direct and indirect jobs in 1996representing 11% of the total employment in the fisheries sector. More recent estimatesreport that jobs have declined to 8,000 due to contraction of the industry in large partbecause of the effects of disease outbreaks. The potential for this industry to once againprovide a large number of jobs and export income makes its development very attractiveto the government of Sri Lanka (FAO, 2008).

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Shrimp farming was started in 1981 in Batticaloa by serandib sea Food Company. It was

collapsed due to some civil unrest conditions. Then after 1990 it was again started inBatticaloa at Thiruperumthurai and Oddamavadi. Natonal Aquaculture DevelopmentAuthority (NAQDA), National Aquatic Resources Research and Development Agency(NARA) and Eastern University were found suitable site selection then it was establishedin 1999 and it prepared zonal planning.

The purpose for identify suitable area for implementation of economically viable andenvironmentally friendly shrimp farm. They identified around 2839 ha of land area nearUppar lagoon, Batticaloa lagoon and Vaharai lagoon this land included in state land andprivate land Now More than 100 farms have established in the Batticaloa district undersemi intensive system.

The farm has been established based on an Indian shrimp farm model. Before 2008 PLwas collected from Puttlam for this reason and it was consumed high cost. Then thebrackish water shrimp hatchery at Puthukudirippu, Batticaloa was established in 2011under the Aquatic Resource Development and Quality Improvement Project of theMinistry of Fisheries and Aquatic Resources Development. Hatchery was established in1.51 ha of land area. Production capacity of this hatchery is twenty million post larvae perannum. . This hatchery is managed by Kings Aqua Services Ltd under a public andprivate partner. NAQDA is providing training for farmers and university students invattavan.

1.1 Theme of the training

An experience within a working place is important to everyone who conduct studies on aprofessional field, to get to know about the working place, duties and responsibilities, toacquire industrial knowledge of relevant field, to understand current situation of the field,to expand the limitation in relevant field and above all to gain professional and personalskills.

Upon that as an aquatic resources technology student of Uva Wellassa University during

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the period of industrial training in to improve the competencies (skills, knowledge,attitudes) related to:

Shrimp farms monitoring Shrimp hatcheries monitoring Laboratory functions those should be provided for the improvement of shrimp

industry

Conservation programmesBesides the field related achievement, training facilitates to enhance the interpersonalskills and to build up personality skills as well which will shape up the performance infuture career.

1.2 Introduction to the organization

The National Aquaculture Development Authority (NAQDA) was established in 1999 bythe Parliamentary Act (No. 53 of 1998) under the provision of the Ministry of Fisheriesand Aquatic Resources

Their duties and targets are:

Provide the sustainable development of aquaculture and fisheries sector Ensure the food security of the nation Increase the living status of nation Earn the local and foreign currency to get economical benefits Build up the entrepreneur and new carrier opportunities

Shrimp farm monitoring and extension unit was established at Batticaloa districtsecretariat in 2008 at. Then it was moved to Puthukudirupu in 2011. It was established toprovide the extension and monitoring services to shrimp farms in the Eastern province.The main purpose for the establishment of this unit is to get old farms well organized,Form cluster and model farms and to solve problems during transporting post larvae.

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They established a hatchery in Puthukudirupu area to overcome post larvae transportationproblem. Then established a cluster farm in Vattavan, Vaharai and established a modelfarm in Air Force camp in Batticaloa to develop shrimp sector.

Roles of Shrimp Extension and Monitoring unit in. Batticaloa are:

Organization the farmers meeting, discuss the problems, and get the suitablesolution.

Establish the model farms and provide the training to farmers and universitystudents for develop the shrimp industry.

Take decision making about stoking date, stoking density, harvesting time andculture time duration.

Visit the each farm and record the observation, specially have at stoking time andharvesting time.

Maintain the related about water quality parameter, survival rate, growth rate,FCR record.

Reduce the environmental issues, the farmers with fishermens conflicts, theillegal fishing activity.

Provide the PL license and Aqua Cultural Management license.

Chapter 2

2 Training work

The training was conducted to study about shrimp extension and monitoring. Duringtraining some tasks were gave by supervisor. This training has been designed to do inPuthukkudiruppu shrimp farm.

2.1 Activities undertaken

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2.1.1 Important parameters of shrimp farm

a) Site selection

The selection of a suitable site always plays a major role in shrimp farming. Thedetermination of a site for shrimp farming is made only after through analysis ofinformation on topography, ecosystem, meteorological and socioeconomic conditions inrelation to farm design, species compatibility and economic viability. Criteria are hereinpresented that could serve as guidelines in judging site suitability.b) Water quality

Water quality includes all the inherent physic chemical and microbiologicalcharacteristics of water. In any chosen site, the pH of the water preferably ranges from 7.5to 8.6. The other equally important chemical characteristic of water is the level of oxygensaturation throughout the water column. Fluctuations in dissolved oxygen level should bepredetermined and the oxygen level is preferably not lower than 4 ppm.

The water must not be too turbid. Water with very heavy silt load can cause siltationproblems in the water supply system. The water is preferably to be rich inmicroorganisms.

Salinity variation is considered a determinant factor in shrimp production. Optimal levelvaries from species to species. For instance, the tiger shrimp (Penaeus monodon) growsfaster at 1530 ppt. The white shrimp (P. indicus and P. merguiensis) tolerate highersalinity ranges (2540 ppt). Ideally, salinity should remain uniform at normal weather andshould not drop abruptly during rainy days.

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Plate 2.1: pH meter Plate 2.2: Refractometer

c) Soil

The types and texture of the soil of the area should be analyzed before settling on a sitefor shrimp farming. Soil samples must be taken at random location, preferably up to adepth of 0.5 meter and subjected to physical and chemical tests to determine the acidity,amount of organic load, level of fertility and physical composition.

The soil at the proposed site should have enough clay contest. This is to ensure that theponds constructed will hold water. Good quality dikes are usually built from sandy clay orsandy loam materials which harden and easily compacted. The dikes will not crack in dryweather. Clay loam or silty clay loam at pond bottom promotes growth of natural foodorganisms. Diking materials made of undecomposed plant matter and alluvial sedimentsshould be avoided. Most ponds developed along the coastal areas with dense mangrovevegetation often have acid sulphate problem during the first few years of operation. Thisis due to the accumulation of pyrites (iron sulfide) in coastal soil. Breakdown of pyrites isminimal in submerged soil.

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During pond construction, the subsoil are dug for dikes

and the pond bottom leveled, the pyrites become oxidized producing sulphuric acid whichacidifies the soil. The pH of water becomes extremely low and hence affecting waterquality and correspondingly reduced natural productivity. Alleviating acid sulphateconditions in ponds requires the use of lime and removal of acid by leaching and flushing.

d) Topography

It is essential to have details topography of the selected site for pond design and farmlayout. Coastal sites where the slopes run gently towards the sea are easier for ponddevelopment requiring less financial inputs since excavation is minimal. Filling anddraining of water likewise is easily facilitated by gravity.

In areas where the above conditions are not available, the use of mechanical pumps maybe resorted. Associated with topography related constraints is the availability of sufficientquantity of soil for dike construction obtained from excavation of ponds or from aboveground bunds. It may prove uneconomical if the site to be developed would requirediking material to be transported from outside the chosen area.

e) Vegetation

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The type of vegetation in the area can be, to some extend, indicative of physical elevationand soil type. Dominance of the mangrove plants Avicennia spp. is an indication of goodand productive soil. Outgrowths of Rhizophora spp. which are usually characterized bydense prop root systems usually signifies soil types that are coarse and acidic.

It is of primary importance to consider density of shrubs at the site. These have to becleared first before any land development can take place. Clearing operation can add up tothe capital outlay.

f) Source of seed

Close proximity of the site to the fry ground is advantageous in that the animals beingcollected for stocking are not subjected to too much transport and handling stress.

Plate 2.4. Nursery rearing tanks Plate 2.5: Seed/PL

g) Accessibility

Accessibility is an important consideration in site selection. Overhead cost and delay inthe transport of materials and products can be minimized.

2.1.2 Pond design and construction

There is no standard design for a shrimp rearing pond. Present day farming practices stillheavily rely on the experience of individual farmers, financial capability and theenvironmental condition prevailing at the site. A shrimp pond from the engineering view

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point is essential an improved shrimp culture pond.

The improved structural design is largely due to the behavior of the Penaeid shrimps. Pmonodon is a benthic animal and it has a habit of gathering along tank walls. Any designto increase the wall surface e.g. adding substrates or an elevated earthen platformextending along the edges of a pond, can promote high stocking densities. An idealshrimp farm is a complex establishment consisting of: various size ponds for nursery andgrow out, water control structures including embankments, supply and drainage canalsand sluice gates, and support facilities such as roads, bridges, living quarters, workshopsand warehouses, etc.

Careful layout of the described facilities and appropriate structural design in relation tothe physical features of the area ensure smooth and effective operational management.

Figure 2.1: Design of Shrimp farm

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a) Size and shape of culture ponds

Rectangular or square ponds are appropriate for shrimp culture. The longest axis of apond should be parallel to the prevailing wind direction. This facilitates water movementgenerated by wind action thereby increasing dissolved oxygen in the water andminimizing water temperature fluctuations in summer or warmer

Table 2.1: Pond types and its size

Nursery pond 500 to 1,000 m2

Grow-out pond - intensive 0.25 to 1.0 ha

- semi-intensive 0.5 to2.0 ha

- extensive 1.0 to 10 ha

The rearing pond must have a minimum depth of 1.0 meter. Most traditional brackishwater ponds for shrimp farming are relatively shallow. To satisfy depth requirement, aditch is constructed along the dike or a central canal between two opposite sides of thepond. The average depth is 1.0 1.2 meters and depth of the platform is 3060 cm.

Pond bottom should be as even as possible free from projecting rocks and tree stumps.The bottom must have a gradual slope from the inlet gate towards the drainage gate. Thesuggested ratio of the slope is 1:500.

b) Supply and drainage channel

Not all shrimp farms are located close to the coast or estuaries. For those that are locatedfar away from the water sources, it is necessary to construct supply and drainage canals.

Conceptually, a shrimp pond must possess separate canals for drainage and supply and foravoiding probable contamination of the water supply. Both supply and drainage canalswould likewise serve as water level control in the pond and as temporary holding areasfor shrimps. It is important that the sitting of the canal systems takes advantage of thenatural waterways within the proposed site.

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c) Reservoir Tank

Reservoir Tank is important for the control of pond environment and storage of watersupply when the water quality is inconsistent or the supply is intermittent.

It is recommended that the area of a reservoir within a farm should be about 30% of thetotal farm area in order to hold a sufficient volume of the water supply. Some farms mayuse part of the reservoir for sedimentation purpose where biological filter feeding

organisms are stocked. The reservoir must have an outlet that can allow total drainage.

d) Sedimentation Pond

Sedimentation pond basically used to remove suspended solids from the waste water.Shrimp Farm suspended solid waste under normal operational condition are primarilycomposed of living plankton cells, feed material and other organic material which do not

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easily settle down. Sedimentation tank can trap 5-10% of such suspended solids. Butduring the harvest time when solid loads are far higher and particular matter is denser cantrap 90% of suspended solids. Thus the sedimentation ponds prevent the release of mostpolluting organic matter that is discharged at the time of harvest to the environment.

e) Water control gate

When designing a sluice gate, it is essential to consider tidal fluctuations and gravity inorder to ensure effective control of the inflow and outflow of water within a given periodof time.

The water gates are classified according to function as main (primary) gate or secondarygate. Main gates are strategically situated at the perimeter and are usually constructed ofreinforced concrete. These are the main structure controlling the quantity of water fordistribution to the shrimp farm.

Irrespective of the material to be used to construct the water gates (e.g. wood, reinforcedconcrete), the following requirements should be met;

A gate should have adequate capacity for the required amount of water to be takenin or drained out;

A gate should be constructed in a position that water can be totally discharged; A gate should have sufficient grooves for placement of filter screens, slabs and

harvest nets;

A gate should be firmly placed at the pond bottom and properly linked with thedikes to prevent seepage and possible collapse.

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A standard gate design consists of tide stern wing, side

walls and bed structure. The side walls are often designed in accordance with the slope ofthe earthen dike. Grooves for slabs are usually set at the inner side of the gate.

Plate 2.7: Water control gate

2.1.3 Pond preparation

Correct pond preparation is crucial to the success of any prawn farm. After all, the postlarvae are being transferred from a hatchery where food is plentiful and conditions wellcontrolled, to "natural" ponds where conditions are much capricious.

In any earthen pond culture system, the bottom soil plays a major role in pond yield. Highorganic matter content in neutral soil often promotes higher primary productivity andhence higher fish yield. Natural food organisms are one of the most important foodsources in ponds. It is rich in protein, vitamins, minerals and other essential growthelements that simple supplementary feed cannot complete. Fish yield in pond can also beaffected by the presence of predators, deteriorating water quality and improper pondmanagement. Hence, pond preparation is a first step towards ensuring a better pond

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production.

The advantage of a well prepared pond is that not only is water quality optimized, butalso is the natural food supply, particularly algae and other phytoplanktons. Indeed, if thePLs are stocked into a pond with poor algae population, they will become stressed. Thatnot only greatly reduces PL growth, but weakens the animals, making them much moreprone to diseases and subsequent death.

After each harvest, ponds are allowed to dry out. At first the waste material in the centreof the pond floor will be back, but with drying out it will turn to gray and then to normalsoil colour. As the bottom dries, it will also crack to a depth of five to ten centimeters orso. This top layer of organic wastes serves as a substrate for microbial activity - includingthat of disease causing organisms - and can contain fish eggs, crab larvae and otherpotential predators. It should not be left in the pond.

Therefore, when the pond bottom is firm enough for a dozer to work on, usually 10 to 15days after harvest, the organic mud is removed with the help of a dozer. It can be donemanually by laborers, but it takes longer time and some areas more costly. When dozer isused, It should only remove material down to the base of the cracks in the soil, whilemaintaining the slope towards the pond outlet. Further ploughing the pond bottom to thedepth of four six centimeters is beneficial, as it enhances soil aeration.

Shrimp culture operation can be grouped into three major categories:

Those that depend entirely on natural food (extensive culture) Those that depend on both natural food and supplementary feeds (improved

extensive and semi-intensive culture

Those that depend entirely on artificial diet (intensive culture)Irrespective of the culture operation used, it is always advisable to prepare the ponds insustaining high natural productivity throughout the culture period.

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Plate 2.8: New pond preparation of Vaakarai farm

a) Soil sampling

Prior to pond preparation, soil samples are collected from the pond bottom and the dikesfor pH and organic matter contents analysis. Soil pH analysis is generally conducted todetermine lime requirement. This procedure is important for newly developed pondswhere the occurrence of acid sulphate soils is common. When acidic soil condition is

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detected, corrective measures can be incorporated in the pond preparation activities.Sampling of soil is not necessary for well-conditioned ponds.

In most soil laboratories, it usually takes one to two weeks before the result can be given.Thus for routine soil pH determination, the shrimp farmer can take upon himself to do theanalysis using a pH meter. To prepare for the analysis, the air-dried soil sample must bepulverized using a wooden mallet or mortar and pestle. It is then passed through a 2-mmmesh sieve and stored in a properly labeled bag or glass jar. The sample is ready for pHdetermination.

b) Leaching

When the pond soil is found to be acidic, it is normally leached. This is done by flushing

and washing the pond bottom with water to leach away undesirable metallic compoundslike aluminum, iron and excess sulfur ions.

Plate 2.9: Leaching in ponds

c) Pond drying

The drying of the pond bottom is the most practical cheap and effective method of

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eliminating undesirable species in pond prior to the culture period. Drying oxidizesharmful chemical substances especially sulfides and facilitates mineralization of organicmatter. The pond is dried until the soil cracks or when it is firm enough to hold one'sweight without sinking more than 5 cm on walking over the surface.

During the process of drying the ponds, other activities must be undertaken. Theseinclude repair of dikes and gates, reconditioning of pond bottom trench, leveling,installation of screens and substrates. Substrate installations such as twigs or coconutfronds at the pond bottom are very important in the first few weeks of culture because thejuveniles have the habit of clinging on vertical surfaces. Aside from that, substrates alsoserve other purposes provide additional surface area for some benthic food organisms,provide shelter against direct sunlight, and reduce mortality of shrimp juveniles frompredators.

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Plate 2.10: Pond drying

d) Tilling

Tilling or ploughing of bottom soil improves soil quality by exposing subsoil to theatmosphere thereby speeding up the oxidation process and the release of nutrients that arelocked in the soil.

Plate 2.11: Tilling

e) Control of undesirable species

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Undesirable species which are pests, competitors and predators consist of fin fishes,crustaceans, mollusks, reptiles, amphibians, birds and mammals. Pests are species thatgenerally do not have direct harmful effects on the cultured stock. In most cases,however, pests are also competitors. Some pests for example are certain species of crabsthat burrow into the dikes. These can destroy the dikes and cause leakages which mayallow the entrance of undesirable species or the escape of cultured stock especially innursery ponds. Others are wood borers and barnacles.

Competitors are species that compete for space, food, oxygen, etc. with the culturedstock. Generally, these are of different species. Competition arises out of the similarity inenvironmental demands which can pose limitations in the cultured species development.Both intra specific and inter specific competitions prevail in any shrimp pond. It isessential to minimize such competition by adequate management procedures in stockingof shrimp fry and prevention of undesirable species from entering the pond.

Predatory species on the other hand, are species that prey on the cultured stock. Thesespecies include snakes, birds, fin fishes, amphibians, crustaceans and mammals. Thepresence of predators is a serious problem for shrimp growers especially in nurseryponds. Predators are generally, but not always, larger than the culture animals.

f) Liming

Liming is the application of calcium and magnesium compounds to the soil for thepurpose of reducing soil acidity. It is usually applied during or after the pond drying stage.

i) Action of limingThe favorable actions of liming are: kills most microorganisms especially parasites due toits caustic reaction, raised pH of acidic water to neutral or slightly alkaline value,increases the alkaline reserve in water and mud which prevents extreme changes in pH,neutralizes the harmful action of certain substances like sulfides and acids, promotesbiological productivity since it enhances the breakdown of organic substances by bacteriacreating a more favorable oxygen and carbon reserves, precipitates suspended or solubleorganic materials and decreases biological oxygen demand (BOD) as well.But Excessive liming, however, can be damaging because it decreases phosphorus

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availability through precipitation of insoluble calcium or magnesium phosphate.

Plate 2.12 Liming

ii) Liming substancesThe chemicals used for liming of soils are the oxides, hydroxides and silicates of calciumor magnesium since these are the ones capable of reducing acidity. Typical limingsubstances are the following:

Calcium oxide, CaOThis is the only compound to which the term lime may be correctly applied. Calciumoxide is variously known as unsalted lime, burnt lime and quicklime. It is manufacturedby roasting calcite limestone in a furnace. Calcium oxide is caustic and hygroscopic andis sold commercially in powder and granular forms.

Calcium hydroxide, Ca(OH)231

Calcium hydroxide is known as flaked lime, hydrated lime or builder's lime. It is preparedby hydrating calcium oxide. It sold commercially in powder or granular forms.

Calcium, CaCO3 and mixed calcium-magnesium carbonate, [CaMg (CO3)2]The carbonates occur widely in nature. Among the common forms that can be utilized asliming substances are calcite limestone which is a pure calcium carbonate and dolomitelimestone which is a calcium-magnesium carbonate with varying proportions of calciumand magnesium. Commercial calcium carbonate is known as agricultural lime. Thecarbonates are the least reactive of the three liming substances.

iii) Advantages of limingThe liming can be extremely beneficial to prawn ponds in terms of pond disinfection andwater quality maintenance such as

It raises the pH and the alkalinity of the acid ponds to desirable levels and helpreduce daily fluctuation of pH in the pond water.

It increases the bottom pH of bottom mud, reducing their affinity for phosphorusand so increasing the availability of phosphorus in the pond water.

It boosts the microbial activity in bottom mud, reducing the rate at which organicmaterial accumulate.

Higher water alkalinity increases the availability of carbon dioxide forphytoplankton.

It can help flocculate suspended clay out of the water column and it can killparasites, their immediate hosts, unwanted competitors and aquatic weeds.

g) Fertilization

One usual way of increasing carrying capacity of a shrimp pond is to improve its naturalfertility through the addition of organic or inorganic fertilizers. Pond fertilization is animportant and necessary step in extensive and semi-intensive methods of farmingoperations.

i) Organic fertilizers

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The most common fertilizers are animal manures, rice bran, compost and sewage.Application of organic fertilizers especially in newly developed ponds is advisablebecause it serves as soil conditioner. The advantages and disadvantages of organicfertilizers are listed in Table 2. The rate of application for shrimp ponds ranges from 500to 2,000 kg/ha.

ii) Inorganic fertilizersInorganic fertilizers are synthetic fertilizers that generally contain concentrated amount ofat least one of the major plant nutrients like nitrogen, phosphorus and potassium. Thesemajor nutrients are expressed on a percentage by weight basis. Nitrogen is expressed at %N and phosphorus as % Phosphorus oxide (P2O5). Commercially available inorganicfertilizers are usually sold with such trade names as 1620-0 (16%N-20%P2O5 -0%K2 O),14-14-14 (14%N-14% P2O5 -14%K2O), 45-0-0 (urea). The rate of application rangesfrom 25 to 100 kg/ha during pond preparation.

2.1.4 Species selection

The shrimp species cultured in Asian countries belong to two genera (Penaeus andMetapenaeus) of the family Penaeidae. Among the dozen species cultured, Penaeusmonodon, P. japonicus, P. merguiensis, P. indicus, P. orientalis and Metapenaeus ensisare the more important ones.

a) Penaeus monodon

Known as tiger or jumbo shrimp, P. monodon is the most common species in SoutheastAsian countries. It is one of the fastest growing species among the various shrimps testedfor culture. In pond conditions, shrimp fry of about 1 g in weight grow to a size of 75100g in five months at a stocking density of 5,000 per hectare. Some were able to grow themto 25 g in 16 weeks in tanks stocked at 15/m2 ; others grew them to 42 g in 210 days inearthen pond and to 35 g in three months in tanks stocked at 15/m2 . The tiger shrimp is aeuryhaline species and grows well in salinities ranging from 15 to 30 ppt. It is hardy andnot readily stressed by handling. Presently, the major supply of fry is still from the wildbut the supply is sparse. Hatchery production of this species still has to depend on wild

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supply of spawn until brood stock in captive condition can be made to mature and spawn.

b) Biology of Penaeus monodon

Wild, gravid P. monodon females spawn in the open sea. It takes about 2 weeks fromhatching of the eggs through the planktonic larval stages until the post larva. Benthic post

larva are found along the cost or in mangrove swamps and other estuarine areas wherethey are collected by fry gatherers for rearing in brackish water bonds up to marketablesize of 16 to 30 pieces per kilogram. Wild fry become juveniles and adults in estuarineareas but return to the sea for spawning.

P. monodon is widespread and abundant. They can be found feeding near the seafloor onmost coasts and estuaries, as well as in rivers and lakes. To escape predators, somespecies flip off the seafloor and dive into the sediment. They usually live from one to

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seven years. Shrimp are often solitary, though they can form large schools during thespawning season. Previously obtained sperm from the male, then attached to the female'sspecialized legs. The female carries the developing eggs until they hatch in early spring.Newly hatched shrimp larvae are small (about 3/16 of an inch, or 5mm), planktonic (freefloating, unable to swim against currents), and bear only a superficial resemblance toadults.

P. monodon are found primarily on or near the bottom, but make daily migrations throughthe water column in search of food. They have been found at depths greater than 1,000feet, but are most frequently captured at depths of 30 to 300 feet. Adult shrimp areomnivorous, feeding on marine worms, small crustaceans, large planktonic organisms,sponges, and dead animal and plant material. In turn, a variety of fish prey on shrimp,including cod, lingcod, hake, flounder, halibut, dogfish, skates, and other bottom fish.

2.1.5 Seed supply

Shrimp fry are generally collected from the wild. However, substantial number can besupplied through shrimp hatcheries.

a) Supply of post larvae from wild stock

Natural abundant supply of naturally occurring post larvae of Penaeid shrimp in manytropical/ subtropical Asian countries has supported a large number of shrimp farms in theregion. About 80% of the small shrimp farmers still depend on wild fry for culture. Fryare collected either through trapping ponds or from natural fry grounds.

b) Seed from hatchery

Shrimp hatchery has become an important supply source for fry. Some hatcheries canproduce shrimp fry all year round as long as spawners are available. An added advantageis that hatchery-bred fry of the same age are almost uniform in size and can be producedin large quantities at any one time. At 1521 days old, the fry are ready for stocking inponds. Although wild fry are ready for stocking in ponds is inconsistent. The hatchery,therefore, is a more reliable seed source.

c) Physical Conditions of Post Larvae

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Visual Observations:

Size variation among the stock should be small, with uniform colour, The movement pattern of the first antenna of the larvae should be V-shaped. The shell should be smooth and clean, free from any algae or protozoa. The abdominal segment should be long not squat. The tails or uropods should spread well when the larvae swim. The rostrum and appendages must be complete and normal in shape. The abdominal segment should be transparent, not opaquely whitish or having

sediment in the body.

The intestine or digestive tract should be full of feed, seen as a brown coloured linealong the back part of the abdomen and tail, unless there is no food available or after along shipment.

The larvae should jump toward solid surfaces when disturbed, such as when the sideof an observation basin is tapped.

The larvae should swim to the sides in a basin of gently swirling water.Microscopic Analysis:

The larvae should be free from fouling organisms such as Zoothamium sp., Epistylissp., as well as detritus.

The gill system should be completely developed. The rostral spines should be 6-7 in numbers. The muscle in the abdominal segment should be fully developed, the muscle should

be completely fill the shell from the gut to the ventral surface.Several stress tests such as salinity shock, temperature shock and exposure to 100ppmformalin are recommended to determine larval quality.

d) Transportation of fry

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There are many ways to transport shrimp fry from hatchery or the

wild to nursery or rearing ponds. Plastic bags very often, shrimp fry are transported inpolyethylene bags with oxygen. The bag (6040 cm) is first filled with 68 liters of freshseawater and then packed with 30005000 fry. The density may be reduced if theexpected transport time is longer. After properly tightening the mouths of the bags, theseare placed in styrofoam boxes or plastic buckets. Water temperature is reduced to about2225C by crushed ice mixed with sawdust on the bottom, side and top of the styrofoambox. Under this condition, the fry may be kept alive for more than 12 hours duringtransportation.

Plate 2.14: Transportation of fry

2.1.6 Grow-out

The success of shrimp farming is measured by its rate of return on investment whichmainly depends upon the yield, capital investment, market price and the production cost.This in turn is affected by a number of factors the most important of which are farmoperation and management.

a) Nursing of fryFry mortality often occurs during the initial period of stocking in ponds. Stress byhandling, transportation and acclimation are among the main causes. Hence, young fry ofsize 0.51.0 g are first stocking in nursery ponds for about one month to 45 days before

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being transferred to grow out ponds.

Nursing of fry can be done either in concrete tank, nursery pond or in net cages installedin deeper ponds or in rivers.

Plate 2.15: Nursing of fry

b) Stocking of fry

Optimization of pond yield largely depends on how the ponds are stocked and theoperational management thereafter. Stocking of fry is an important operational function.Optimum stocking density depends on the stocking size, natural mortality, pondproductivity and culture systems used.

c) Acclimation

Shrimp fry are very sensitive to abrupt change in environmental conditions such astemperature and salinity. Long duration of transportation always increase watertemperature of the containers with shrimp fry. Fry should therefore be acclimated to thepond conditions before being released into the rearing ponds.

Shrimp fry are acclimated to pond water condition by gradually mixing container waterwith water from the pond. Alternatively, plastic bags containing the shrimp fry areallowed to float in the pond until water temperature stabilized and then release to the

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pond slowly.

Plate 2.16: Acclimation area

d) Stocking time

The fry should be stocked preferably in the early morning (07001000 hours) or late inthe evening (21002400 hours) when the pond water temperature is low.

Plate 2.17: Stocking to the pond

e) Stocking rate

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The decision on how many shrimp fry a pond should be stocked depends on the carryingcapacity of the pond as well as the required harvesting size. The latter is a decision basedon economic returns. The basic principle is that pond capacity should be optimized toproduce the best economic returns. Optimal stocking density can be determined based onfield experiments.

It is apparent that stocking density at 2/m2 gives maximum yield as well as best economicreturns considering the preferred harvesting size (3035 g) for export as well as domesticmarkets.

Table 2.2: Stocking density of shrimp in different culture

Species Extensive Semi-Intensive Intensive

( 103 individuals/ha)P. monodon 510 2050 50300

f) Routine pond management

After initial stocking, routine checking of pond conditions should be done every morningto monitor for physic chemical parameters, physical condition of embankment, watersupply and drainage canal, and occurrence of undesirable species as well as the behaviorof cultured stocks. The early morning hours are critical for monitoring oxygen regime ofpond water. It is also important to inspect the feeding trays to verify that the feed giventhe previous day were consumed. If the feeds were not fully consumed, the possibleexplanation should be found and feeding rate adjusted accordingly.g) Water management

Frequent change of pond water is needed to maintain water quality. The process alsohelps to introduce new food organisms into the pond and stimulate molting of shrimp. In

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stagnant water, decomposition of accumulated organic wastes or depletion of trace metalsmay affect shrimp growth. The water in the pond can be changed through tidal flows orby means of a mechanical pump.

Tidal exchange of pond water is normally practiced in traditional shrimp farm. Water inthe pond is drained to one half of the pond level during low tide and is replenished duringrising tide. The exchange is only affected within 5 7 days during spring tide. Pondfertilization has to take place after the last day of the water exchange cycle.

Water pumps of various capacities are used to replenish pond water in semi intensive andintensive culture operations.

For semi intensive culture method, the pump is used only during neap tide while tidalwater facilitates exchange during spring tide. About 50% of pond water is changed duringeach replenishment. For intensive culture methods, frequent changes are essential toremove or reduce water contamination due to decomposition of uneaten food and also tomaintain the pond oxygen levels in pond water. Hence, water at the pond bottom shouldbe replaced during each change of water. Quality of water can be effectively maintainedin intensive culture method by changing of the pond water daily or adopting a flow-through system.

h) Sampling of stocks

Regular sampling of shrimp stocks in pond is highly necessary to monitor, their growthperformance. This is especially important for adjust the amount of feed used according toshrimp size and standing crop. This is done through periodic sampling of the shrimp todetermine their body weight.

In the case of Penaeid shrimps, seining is not possible since these species are usuallyburrowing or wandering types. It is therefore difficult to obtain a representative sample.However, since these are hardy species, a cast net has proven to be an excellent samplinggear. Usually ten casts is sufficient to get a representative sample of one hectare pond.The dimension of a cast net should be measured to determine the area covered in order tocalculate the total stock in the pond.

Sampling in early hours of the morning or at night is preferable as the shrimps are more

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active during these periods and are more evenly distributed that during hot sunny day. Forlarge pond, 1520 casts may be necessary to obtain a more accurate average.

2.1.7 Water quality management

In any shrimp farming, management of water quality is of primary considerationparticularly in ponds with higher stocking rates. Degradation of water quality isdetrimental to shrimp growth and survival. Good quality water is usually defined as thefitness or suitability of the water for survival and growth of shrimp.

a) Salinity

Younger shrimps appear to tolerate a wider fluctuation of salinity than the adults. Thepost-larvae of many Penaeid species can tolerate wide salinity fluctuation which has littleeffect on their survival or growth. In pond condition, P. monodon can tolerate wide rangeof salinity from as low as 5 ppt to a high of 40 ppt. Many Metapenaeus also tolerate highsalinity. P. merguiensis and P. indicus prefer brackish water while P. semisulcatus and P.japonicus require more saline condition for growth (2732 ppt).

Due to high evaporation rate in some countries, salt

concentration in ponds gradually increases during the summer months. Salinity mayincrease to beyond 40 ppt and thus retard growth. This should be taken into considerationwhen brackish water species are used since salinity may increase above their limit oftolerance. In such cases, the species cultured should be changed during the summermonths to conform to increasing salinity or the water should be changed frequently eitherby pumps or through tidal exchange.

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Plate 2.18. Measuring salinity level

b) pH

The pH of the pond water is indicative of its fertility or potential productivity. Water withpH ranging from 7.5 to 9.0 is generally regarded as suitable for shrimp production. Thegrowth of shrimps is retarded if pH falls below 5.0. Water with low pH can be correctedby adding lime to neutralize the acidity.

Water of excessive alkalinity (pH values > 9.5) may also be harmful to shrimp growthand survival. In ponds which are excessively rich in phytoplankton, the pH of pond waterusually exceeds 9.5 during late afternoon. However, at daybreak, the pH is usually lower.Excessive plankton growth can be corrected by water exchange.

c) Dissolved oxygen (DO)

Maintenance of adequate level of dissolved oxygen in pond water is very important toshrimp growth and survival. Prolong exposure to the stress of low concentration ofoxygen lowers their resistance to disease and inhibits their growth. In most cases, oxygendepletion often resulted in mass mortality (anoxia) of shrimp stock. This is particularlycommon in intensive culture operation.

Dissolved oxygen in the pond water comes from two sources. Most of it comes as a by-product of photosynthesis. The other source is from the diffusion of atmospheric air. Theamount of dissolved oxygen in the pond water is affected by many factors particularlywater temperature, respiration and the level of organic matter. In tropical shrimp pond,the oxygen level in the pond water is normally low because of the higher temperature.However, tropical species are able to adapt to lower oxygen concentration than theirtemperature counterparts.

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During daytime, more oxygen is produced through photosynthesis than is removed fromthe water by the respiration of animals. At night, both plants and animals continue torespire while oxygen is being added to the water only from the atmosphere. In someinstances, the respiratory demand under certain circumstances cause total depletion ofoxygen especially at daybreak causing anoxia of the cultured animals.

Depletion of DO in the pond can be controlled by the following measures, Waterexchange through renewal of pond water with fresh water either by tidal flow orpumping, Installation of aeration system. In the design of pond layout, it is essential toconsider maximal utilization of the natural environment to maintain higher dissolvedoxygen content in pond water such as: Orientation of the long axis of the pond with theprevailing wind.

Construction of larger pond to allow a greater contact of water surfacewith atmospheric air.

Promote wind action on the pond in facilitating water movement andoxygen diffusion.

Avoid planting of trees on dikes.

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d) Nitrogen compound

Nitrogen in pond exists in different forms such as nitrate, nitrite, ammonia and variousforms of organic nitrogen. Organic nitrogen ranges from relatively simple dissolvedcompounds such as amino acids to complex particulate organic matter. Nitrogen occurs inthe mud in the same form that exists in water. In pond culture activities, ammonianitrogen (in the form of un-ionized ammonia) is considered important since thiscompound is toxic to aquatic animals at certain concentrations. An ammonium ion whichis another form of ammonia nitrogen is harmless except at extremely high concentrations.

Ammonia nitrogen is a product of fish metabolism and decomposition of organic matterby bacteria. The pH and temperature of the water regulate the proportion of totalammonia which occurs in un-ionized form. The highest concentration of total ammonianitrogen usually occurs after the peak of phytoplankton bloom when most of them died.

e) Temperature

Water temperature plays a very important role in regulating the activities of the culturedanimal. The rate of chemical and biological reactions is said to double every 10Cincrease in temperature. This means that aquatic organisms will use twice as much

dissolved oxygen and chemical reactions will progress twice as fast at 30C than 20C. Itfollows therefore that dissolved oxygen requirement of aquatic species is higher inwarmer than in cooler water. Many Penaeid species are tropical or subtropical species.The optimum temperature is about 2530C and hence many of the species such as P.indicus, P. monodon and P. merguiensis can be cultured throughout the year while P.japonicus and P. orientalis are limited to the summer growing seasons only.

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f) Hydrogen sulfide (H2S)

Hydrogen sulfide can severely affect shrimp growth in pond. H2S is produced bychemical reduction of organic matter that accumulates and forms a thick layer of organicdeposits at the bottom. The bottom soil turns black and a rotten smell is discharged ifdisturbed. High levels of hydrogen sulfide would affect directly demersal or burrowingshrimps such as P. monodon. At levels of 0.10.2 ppm in the water, the shrimps appear toloss their equilibrium and die instantly at a concentration of 4 ppm.

g) Turbidity level

Turbidity level is determined by the soil particles & planktons. It is determined by FTUunit. Shrimps can bear 150 FTU. Most proper amount is under 30 FTU. It is measured bythe Sechi Disk. Normally the measurements are 30- 400cm nearly.

2.1.8 Feeds and feeding

One of the most important operational functions in shrimp culture is the provision ofadequate food supply to ensure that the cultured animals attained the desired harvestingsize within the targeted time frame. In semi intensive culture operation, supplementaryfeeds are given while natural food organisms remain the major food source. In intensive

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culture operation, shrimp growth is completely dependent on artificial diets.

a) Natural food in pond

Natural food organisms were allowed to grow in well prepared pond fertilized withorganic or inorganic fertilizers. These food organisms in the form of benthic blue greenalgae, diatoms, green algae and various species of microscopic zooplankton and microbenthos serve as the natural food of the cultured shrimp.

Phytoplankton Fertilization in pond promotes growth of microscopic plants known asphytoplankton, these primary producers serve as the main food of zooplankton andbenthic organisms which in turn become the food of shrimps. The presence of yellowishgreen color in pond water signifies good growth of desirable planktonic organismsconducive for shrimp growth.

b) Supplemental feeding

As the shrimp grow, consumption increase and the natural food in the pond becomeinsufficient. Thus, many shrimp farmers provide supplemental feeds. The types of feed

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used are:

Moist/wet feeds - These are freshly prepared feeds using locally availableingredients.

Dry pelleted feeds - Pelleted feeds are available commercially to be used assupplementary or full feeds of shrimps. These are also prepared using locallyavailable ingredients. Usually, commercial pellets are brought in bulk

c) Types of Feed

The quality of the prawn feeds can be determined by the following:

Pellet size and colour should be consistent.

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There should be very minimum dust present. The pellet should not float when chopped in water. The feed should have a good smell, not a musty odour. The pellet should be dry The pellet should remain in one piece after 2 to 3 hours immersed in water, but

not longer than 8 hours.

Feed ingredients should be high quality and free from toxicants or pesticides.A final check on quality should include taste the pellets. They should taste sweet from thefresh fish meals: if a numbness is felt on the tongue then the fish meals used was no fresh.

Grow out prawn feeds are of four types, mainly.

Post Larvae Feed Starter Feed Grower Feed Finisher Feeds.

Each differs from the other in terms of size and protein content. Post Larvae feeds areknown to be containing the highest protein content, followed by starter, grower andfinisher with the lowest protein content.

Normally the type of the feed to be given is determined by the culture days or based onthe average body weight of the prawns in the pond. Post larvae feed is given in the first15-20 days of culture. The starter feed is then introduced until prawn attains an averagebody weight of 4-5 grams. Grower feed starts from 5 grams and continued until 20-25grams. From that size onwards the finisher feed is given up to the time of harvest.

d) Feeding method

Supplemental feeds may be given by broadcasting, through feeding tray. Broadcastingmethod is carried out by spreading the feeds evenly into the pond surface. For biggerponds, the use of flat-bottom boat is needed so that the mid-portion of the pond can bereached.

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Feeding trays containing the apportioned feeds are placed strategically at different parts ofthe pond. The trays vary in size from 110 m2. The common materials used are wovenbamboo strips or polyethylene screen. The trays are usually tied at four corners andsuspended into the water column. The use of feeding tray prevents feed wastage. At thesame time, the size and condition of shrimp can be checked and their consumption rateestimated based on the left-over feed in the tray. The disadvantages however, are thatwhen insufficient feeds are given or insufficient trays are used, the bigger and strongershrimps might prevent the weaker and smaller ones from feeding. If there are manycompetitors in the pond, they might consume the feeds before the shrimps can get hold ofthem. Hence, in order to minimize the above mentioned situation, a combination ofbroadcasting and feeding tray methods are usually employed.

e) Feeding rate and frequency

The common feeding frequency adopted is 25 times a day. Most culturists feed their

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stock every morning and afternoon only. However, experiments have shown thatapportioning daily feed ration several times a day improve feed conversion efficiency as itreduces feed wastage, ensures feed quality and more even distribution to the stock. If thestocks are to be fed 5 times a day, two should be given in daytime and 3 at night as theshrimps are more active when dark.

f) Storage of Feed

During storage, quality, weight and economic losses and health risk occur in feed stuffsand feeds. These losses arise from the foraging activities of insects, micro-organisms andanimals; improper handling; and physical and chemical changes, all of which areinterrelated. Stored feed undergo chemical changes that alter flavour and nutritive value.

Feed should be kept in cool, dry clean place. A low moisture content (less than 10%) ofthe feed stuffs and feeds coupled low humidity (less than 70% relative humidity) of thestorage area will provide protection against rain and insulated against scavenger pests.

Continues high temperature accelerates chemical degradation, especially vitamindestruction and development of rancidity. The storage area must be away from directsunlight. The feeds and feed stuffs then should be stored in the least possible time. Thereshould be a rapid turn over of goods that those procured first are to be used first, andthose that arrived last be used last.

g) Operation of AeratorsIt is not necessary to run the aerators continuously especially in the early part of the

production cycle. The length of time the aerators have to be used is dictated by thedissolved oxygen level and the condition of the pond bottom. Table 8 provides a roughguide to the operation of aerators in a well-managed pond.

It may not always be necessary to run all the aerators in order to clean the pond. Forexample, after 90 days the action of the aerators used to oxygenate the ponds at night mayallow fewer aerators to be used during the day. Reducing the number of aerators reducedrunning costs so they should not be used unnecessarily.

The data on the above table is only intended as a guide in cases where the oxygen drops

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below 4 ppm, there is a plankton crash, or chemical treatments are being used, all theaerators should be run all day except when feeding. In the cases the shrimp should not befed for short periods and the aerators should be run continuously.

2.1.9 Chemicals used

a) Super PS

Benefits

Decrease H2S in the water column and soil Increase the content of Oxygen in the water & soil Promotes the occurrence of non pathogenic bacteria over pathogenic types Prevent the occurrence of diseasesMethod of Application

At early stage apply 0.5ppm/weekly (for 1 Ac pond with 1m water depth 2L of SuperPS for weekly)

At middle stage apply 1ppm/weekly (for 1 Ac pond with 1m water depth 4L of SuperPS for weekly)

At last stage apply 1-2ppm/weekly (for 1 Ac pond with 1m water depth 4L-8L ofSuper PS for weekly)

b) Super NB

Benefits

Utilizes NH3 and NO3 in water and soil Prevent the formation of pathogenic bacterial phase Digest the un used organic substances including proteins, carbohydrates and lipids

Method of Application

During early stages, apply 0.5ppm Super NB times per week52

During middle stage apply 0.5- 1ppm Super NB every 3days During later stages, apply 1-1.5ppm Super NB every week

c) Bion

Benefits

Helps the prawns in digestion Improve FCR Promotes growth rate production Reduces the incident of diseases in culture animals

Method of Application

5g of BION mix with 1Kg of shrimp feed by using 20ml of squid oil or fish oiland 100ml of water as daily feed additive

To solve white gut etc 5-10g/Kg feeds Mix well and leave for air drying 30 minutes

d) Vitazyme- 288

Benefits

Stimulate shrimp appetite Improve growth rate Reduce FCR Improve shell formation and improve cronic soft shell problem

Method of Application

Dilute 10g VITAZYME- 288 in 100ml water and mix to 1kg shrimp feed Use in every meal every day as per needs especially to improve shell hardness &

15 days prior to harvest.

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2.1.10 Harvesting and preservation

The stocks are usually harvested upon reaching the marketable size (about 30pcs/kg).Harvesting may be done completely at one time or partially depending on demand.Complete harvesting is usually undertaken by the use of a bag net installed at the drainagegate of the pond. The shrimps that go with the drained water are collected at the bag netand the remaining ones are hand-picked when the pond is completely drained. Theshrimps should be harvested only when they are not molting because newly moltedshrimp have soft shell and fetch lower price.

Partial harvesting is normally practiced in culture operation with higher stocking density(i.e. in semi-intensive or intensive culture). The stock, upon reaching the marketable size(30 g and above) can be harvested by the use of selective harvesting net.The selective harvesting net is a modified shrimp trap net installed in the pond with meshsize big enough to retain the bigger shrimps. Several harvesting nets may be installed atvarious pond locations. This harvesting device is more efficient at night. Selectiveharvesting improves pond yields because it reduces intra-specific competition thus givingchance to the smaller ones to grow better.

Upon harvesting, the shrimps should be washed and placed immediately in chilled water(1015C) for about 15 minutes. They are then packed in styrofoam box with alternatelayers of crushed ice at a ratio of 1:1. Smaller styrofoam boxes are preferred to facilitatetransportation. If bigger styrofoam boxes are used, it is better to fill up the box withchilled water, shrimps and ice to avoid physical damage on the shrimps at the bottom.

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Plate 2.24: Harvesting

a) Timing of Harvesting and Selling

The timing of harvesting depends on the condition of the shrimp in the pond and also themarket price. Under normal circumstances, the shrimp will be sampled by a cast net fromdifferent areas of the pond to determine their average body weight and general condition.The proportion of soft shell shrimp should not be more than 5% at the time of harvest.This proportion could be obtained by scheduling the harvest halfway between twomoultings. The time of moulting is indicated by the presence of exuviate in the pond.For example if the average body weight of the shrimp is 30 g, then the harvest should beplanned for 7-8 days after the exuviae are observed, as the next moulting cycle can beobserved after 14-16 days. Harvested shrimp should be chilled, iced and transported tocold storage or processing plants in less than 10 hours.

2.2 Learning outcomes

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Gain knowledge in shrimp industry in Batticaloa Study the role of shrimp farming monitoring and extension unit in Batticaloa

District

Study about shrimp aquaculture Gain knowledge about hatchery management Gain knowledge about critical things in shrimp farming Study about brackish water cluster and model farm Gain knowledge about best management practices in shrimp industry Learn about the conditions should be provided during the storage and transportation

of PL and fry

Find out the current issues and possible solution for them at the farm

2.3 Problems identified, Possible Solutions and recommendations

In the farm there is a storage tank but they not well utilize it. When exchanges water,they directly get the water from lagoon. They were not stored in storage tank beforeintake water to tank. They also do not follow any water treatment procedure to treatwater before use them for shrimp culture.

In the sediment tank no more mangroves are there. Only few plants in the sedimenttank. They not well manage the mangroves in the sediment tank. It is better tomaintain some more plants in the sediment tank. Sediment tank is use to treat waterwhich used for cultivation before enter the lagoon. Mangrove plants help very well inwater treatment.

On the boundary and boundary lines of pond want to maintain grasses. Here there are56

grasses on the boundary but they not manage well. All grasses are dried.

In a shrimp farm bio security measures are very important. They have good biosecurity measures. They have foot bath and bird nets. But in some ponds bird linessare not properly maintained. Some bird nets were broken. Flamingo like birds canenter to pond. It may cause any disease to pond. So it is essential to maintain all biosecurities well in that pond.

There are some dogs and cats around the office room. It may enter to pond. It cancause any disease to shrimp.

In this farm water quality checks only in the morning. It is better to check also inevening to determine any fluctuations in water quality.

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Chapter 3

3 Conclusions, future scopes for training and research

3.1 Conclusion

Shrimp farm industry is a developing industry in Batticaloa. Training on shrimp extensionand monitoring unit help to improve knowledge in shrimp industry.

During the industrial training gathered lot of knowledge about shrimp farming and shrimphatchery management. Knowledge was gained by theoretically and practically as well.Through this training could be able to develop many skills such as communication skills,inter personal skills etc. This experience will help to success in future career.

3.2 Future scopes for training and research

The training programs and researches are important in identifying the drawbacks,weaknesses and strengths of an organization. Thereon researches can be conducted onseveral criteria at farm and hatchery as well;

To provide more hygienic and aseptic handling of culture organisms To safe guard the culture organisms from natural threats such as heavy raning and

flooding and predator animals

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To determine the most suitable water quality parameters for culture organisms

Reference

Fisheries and Aquaculture Organization FAO 2009. National Aquaculture SectorOverview Fact Sheets text by Siriwardena, P. P. G. S. N. FAO Nationalaquaculture sector overview Sri Lanka.

Jahncke, M.L., Browdy, C.L., Schwarz, M.H., Segars, A.,Silva, J.L., Smith, D.C.,& Stokes, A.D. 2001. Preliminary application of Hazard Analysis Critical ControlPoint (HACCP) principles as a risk management tool to control exotic viruses atshrimp production and processing facilities.pp 279- 284.In C.L. Browdy and D.E.Jory. (eds.) The New Wave: Proceedings of the Special Session on SustainableShrimp Farming. The World Aquaculture Society. Baton Rouge, LA, USA.

Jayasinghe, J.M.P.K. 1995. Shrimp aquaculture and environment. Sri Lanka studyreport. Bangkok, Asian Development Bank and the New York of AquacultureCenters in Asia- Pacific, RETA 5534, 32p.

Jayasinghe, J.M.P.K. and Maclntosh, D.J. 1993. Disease out- breaks in the shrimpculture grpw out systems in Sri Lanka. Journal of Tropial Agriculture Research, 5,336- 349.

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Wijegoonawardena, P.K.M., and P.P.G.S.N. Siriwardena, 1996.Srimp farming inSri Lanka: health management and environmental considerations. In healthManagement in Asian Aquaculture.Proceedings of the Regional ExpertConsultation on Aquaculture Health Management in Asia and thePacific.R.P.Subasinghe, J.R. Arthur & M. Shariff (eds), p. 127-139, FAOFisheries Technical Paper No. 360, Rome, FAO. 142p

Munasinghe, M.N., Stephen, C., Abeynayake, P. and Abeygunawardena, I.S.2010. Research Article - Shrimp Farming Practices in the Puttallam District of SriLanka: Implications for Disease Control, Industry Sustainability, and RuralDevelopment. Veterinary Medicine International. Volume 2010 (2010), ArticleID 679130, 7 pages

Appendices

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