Technology We Use

   Pond Fish Farming Integrated Fish Farming  Fish Seed Production Fresh Water Prawn Culture

 Pond Fish Farming   

Fish Farming is an age old activity and in practice from ancient times. The concept of composite fish culture was developed by ICAR in late seventies under a coordinated composite fish culture project. This comprises the culture of 3 indigenous species of fish viz. rohu, catla and mrigal and 3 exotic fish i.e silver carp, grass carp and common carp, keeping in view their different food habit and habitat. This practice has been very well accepted by the farmers of Haryana as its cultural practices are analogous to agriculture.

The successful fish culture requires ploughing of pond, addition of manure, stocking of fish seed; eradication of unwanted aquatic plants and animals, watering the pond; harvesting the crop and marketing of the produce. The fish culture technologies and economics are simple and understandable to the fish farmers. To produce one kilogram fish, the requirements are:-

 

- one cubic meter water- three number fish seed- one kilogram manure and 100 gm inorganic fertilizer- one kilogram supplementary feed- and one year time

 

Cost of production of fish is Rs. 15/kg and the sale price on an average is Rs.30/- per kg. A net profit of Rs.61,000 per hectare per year is obtained, The pond fish culture practice is being adopted by farmers in all the districts of the state. There are 8,065 fish culture units having an area of more than 12,883 hectares in the state. The ownership of these ponds vested with the panchayats. Panchayat leases out their ponds to the farmer's for fish farming. These village ponds are generally visited by cattle for drinking water. The cattle refuse dung and urine in the pond. The organic waste released by the cattle are recycled into manure and help in the production of plankton which is basic food for fish. Thus all the village fish culture ponds in Haryana are the good example of fish cum cattle farming. With the passage of time, the farmers have modified the technologies as per the need. Generally Rohu,catla, mrigal and common carp are used for culture. The stocking density is kept at 20000 fish seed per hectare. Farmers have adopted the technique of multiple harvesting. which give better returns. Govt. provides 20% subsidy to general category while 25% to scheduled caste fish farmers for excavation of new pond/ renovation of old pond and fisheries inputs.

 

 

Economics of Fish Farminga) Expenditure

  Construction of Pond,Water Supply Channel, Installation of Tubewell/Renovation/Lease Amount

  Electricity & Water charges  Cost of 250Kg Lime  2000 Fish Seeds  100 Quntals Organic Fertilizer  250 KG Urea  500 KG Single Super Phosphate  Supplimentry feed  Medicine, Fishing, Watch & Ward

TOTAL EXPENDITURE   

b) Income  Sale of 4200 KG Fish   

c) Net Income (B-A)   

Note:- The Income may vary on the productivity and market price of a pond 

 Integrated Fish Farming   

Fisheries Department provides technical and financial assistance for integrated fish farming. The Integrated fish farming practices utilize the waste from different components of thc system viz. live stock, poultry, duckery, piggery and agriculture byproducts for fish production. 40-50 kg of organic wastes are converted into one kg of fish, while the pond silt is utilized as fertilizers for the fodder crops, which in turn is used to raise livestock. The system of integrated farming is very wide.

The system provides meal, milk, eggs, fruits, vegetables, mushroom, fodder & grains in addition to fish. It utilizes the pond dykes which otherwise remain unutilized for the production of additional food and income to the farmer. The possible'integrated farming systems are given below:

  a) Fish cum Agriculture System   b) Fish cum Animal System  

 Fish cum Paddy CultureFish cum water chestnutFish cum Pappaya

 Fish Cum DairyFish cum Pig FarmingFish cum Rabbit Farming

 

 

Fish cum MulberryFish cum Mushroom  

Fish cum PoultryFish cum Duck Farming

         Fish cum Dairy

Fish-cum-Dairy Farming is considered as an excellent innovation for the use of organic wastes. Use of cow/buffalo manure in fish farming is a commonly prevailing practice. On an average, one cow/buffalo excretes 12000 kg of dung and 8000 litre urine per year. The cattle faeces and urine are beneficial to the filter-feeding and omnivorous fishes. On an average, 3-4 cows/buffaloes can provide sufficient manure to fertilize one hectare pond. In this system, farmer gets milk, fish and calf as well, which increases revenue and reduces input costs. The system gives a net profit of Rs.1,14,000/- per year from one hectare land.

Economics of Fish cum Dairya) Expenditure Rs.

  Construction of Pond,Water Supply Channel, Installation of Tubewell/Renovation/Lease Amount

20000

  Electricity & Water charges 10000  2000 Fish Seeds 1500  Construction of Shed for Animals (Rs. 80000/- for 10 years) 8000  Purchase of 5 Murrah Buffalo (Rs 20000/- for 5 years) 20000  13000 Kg Animal Feed 78000  Medicine for Animals & Fishes 2000  Labour Charges 20000

TOTAL EXPENDITURE 159500     

b) Income  Sale of 4200 KG Fish 126000  Sale of 10000 Ltr. Milk 140000  Sale of 5 Young ones of Buffalo 7500     

c) Net Income (B-A) 114000 

Note:- The Income may vary on the productivity and market price of a pond 

Fish cum Piggery

The pig dung as an organic manure for fish culture has certain advantages over cattle manure. The waste produced by 20-30 pigs is equivalent to one ton of Ammonium Sulphate applied to the soil.The pigs are fed largely on kitchen waste, aquatic plants and crop byproducts. At present, fish-pig integration is practiced in all the developing countries. Several exotic breeds of pigs have been introduced in the country to augment pork production. The popular races are the white

Yorkshire,Berkshire and Landrace. The pigsties should provide adequate protection from adverse weather conditions. A run or courtyard adjacent to the pig house is essential. The size of the pig house depends on the number of pigs to be reared. Floor space is provided @3-4 m2 for every pig weighing 70-90 kg.The pigsties are built mostly at the pond sites and even over the ponds. The washings from the pigsties containing dung and urine are either channelised directly into the pond or composed before its application. The boars, sows and finishing stocks are housed separately. Maize, groundnut, wheat- bran, fishmeal, mineral mixture provide base for concentrated feed mixture. In advanced countries,garbage is widely used to economize pork production and provided after pre-cooking when pig dung is applied to a pond. It enhances the biological productivity of the pond. A portion of dung is directly consumed by some fish also. The excreta voided by 35-40 pigs is found adequate to fertilize one hectare of water. Integrated fish-pig farming is a viable and feasible scientific approach to augment fish production at low cost. The net income in this integration from one hectare of pond is Rs.l,39,000/-.

Fish-cum-Poultry

The droppings of birds in this system are utilized to fertilize the pond. Poultry litter recycled into fish pond produces 4500-5000 kg fish per hectare per year. Broiler production provides good and immediate return to the farmers. Success in production depends mainly on the efficiency of the farmer, experience, aptitude and ability, in the management of the flock. This involves procurement of better brood stock, housing, brooding equipment, feeders, water trays and management practices,which also includes prevention and control of diseases. The poultry litter is applied to the pond in daily doses at a rate of 40-50 kg per hectare. The application of litter may be deferred during the days when algal blooms appear in the ponds. One adult chicken produces about 25 kg of compost poultry manure in one year. 500-600 birds would provide sufficient manure for fertilization of one hectare of fish pond. Farmer can get a net income of Rs.l,37,157/- from one hectare of pond in one year. Govt. provides financial assistance to the farmers for promoting this system.

Economics of Fish-cum-Poultrya) Expenditure Rs.

1Construction of Pond,Water Supply Channel, Installation of Tubewell/Renovation/Lease Amount

20000

2Electricity & Water charges 100003Construction of Poultry Shed ( Rs.80000/- for 10 years) 8000

4550 Chiks 2750522500Kg Poultry Feed 900006Medicines for Fish & Poultry 50007Fishing, Sale of Poultry Birds & Labour 20000

TOTAL EXPENDITURE 157250     

b) Income    Sale of 4200 KG Fish 126000  Sale of 118750 Eggs 148437  Sale of 500 KG Poultry Birds 20000  Total Income 294437   

c) Net Income(B-A) 137157   

Note:- The Income may vary on the productivity and market price of a pond 

Fish cum Duck farming

Fish cum Duck Integration is most common in the developing countries. This type of integration is not popular in northern states of India. Ducks are of several types and Khaki Campbell is recommended for fish-cum-duck integration Fishpond being a semi-closed biological system with several aquatic animals and plants provides an excellent disease-free environment for the ducks. In turn, ducks consume juvenile frogs, tadpoles and dragonfly etc. there by making a safe environment for fish. Duck droppings go directly into the pond, which in turn provide essential nutrients such as carbon, nitrogen and phosphorus that stimulate growth of natural food organisms. Ducks also help in aerating the pond water, alongwith bottom racking. About 300 ducks are enough to fertilize a pond of one hectare. The system results in a net income of Rs. 77500/- per year per hectare. However, due to difficulty in marketing of eggs and duck meat, the system is not very common in the state.

Fish cum Horticulture

Integration of fish cum flowers, fruit plants, vegetables and mushroom can be takcn up. The pond humus is used as manure for plantation. Pond water can be used for plants which is rich in nutrients, thereby decrease the cost on inorganic fertilizers. The pond dykes are used for the plantation. The culture practice can be taken up as per suitablity to the location i.e. location specific. The economics also varies and depends on the type of plantation.

     

 Fish Seed Production  

  Quality fish seed is the pre-requisite for successful fish farming. Department is using the techniques

 

of hypophysation for the production of fish seed of culturable varieties. The breeding season of common carp fish in Haryana is February-March every year where as the breeding season of other species is monsoon season. Brood stock of required fish are maintained and sex-wise segreggate is made two month before. The pairing is made and injected with calculated dose of pituitary gland or ovaprim, ovatide or ovpal is injected to male and female fish. Within the 6-8 hours of the injection eggs from female and sperm from male are released in the water. The fertilizer is external. Normally one kg fish releases about one lakh eggs. The hatchlings are known as spawn. The spawn is reared in the nursary pond. After 15 days, the spawn attains the size of 25 mm and ready for stocking in the pond. More than 50 lakh fry can be produced per hectare fish seed farm in both the seasons in a year. The income from sale of fish seed is Rs. 3.25 lakh approx. per year @ Rs. 6500 per lakh. Fisheries department provides technical and financial assistance for setting up of ecotype hatchery and fish seed rearing units.

 

Economics of Fish Seed Productiona) Expenditure Rs.

  Construction of Eco Hatchery, Ponds, Water Supply Channel, Installation of Tubewell ( Rs/- 8 Lakh for 10 Years)

80000

  Electricity & Water charges 50000  Cost of 250 Kg Lime 750  1500 Kg Brood Stock 60000  100 Quntals Organic Fertilizer 5000  250 KG Urea 1250  500 KG Single Super Phosphate 1500  Supplimentry feed 50000  Injecting Material, Medicine, Fishing, Watch & Ward 25000

TOTAL EXPENDITURE 273500     

b) Income  Sale of 500 Lac. Fish Spawn 200000  Sale of 50 Lac. Fish Fry 325000  Sale of Spent Brood Stock 20000  TOTAL 545000     

c) Net Income (B-A) 271500   

Note:- The Income may vary on the productivity and market price of a pond

 

Location of Fishery Seed FarmsGovernment Farms

Sr. No. Location of the Farm Total Land Area (in hectares)

Total WaterArea (in hectares)

1 Jansui (Ambala) 1.00 0.94

2 Sidpura (Karnal 3.00 1.98

3 Jyotisar (Kurukshetra) 14.60 6.93

4 Rohat (Sonepat) 3.00 1.42

5 Damadama (Gurgaon) 6.61 1.25

6 Badkhal (Faridabad) 6.50 3.50

7 Lisana (Rewari) 4.81 1.93

8 Sampla (Rohtak) 6.44 3.24

9 Kakroi (Sonepat) 4.52 2.31

10 Jhajjar 4.00 1.42

11 Tohana (Fatehabad) 4.20 1.60

12 Hisar 21.80 7.17

13 Dadupur (YamunaNagar) 0.60 0.08

14 Mundri (Kaithal) 2.00 0.90

15 Ottu (Sirsa) 2.80 1.30

Private Farms

Sr. No. Location of the Farm Total Land Area(in hectares)

Total Water Area(in hectares)

1 Dherdu (Kaithal) 2.00 1.80

2 Bhutana ( Karnal) 10.00 8.00

3 Mandheri (Kurukshetra) 10.00 6.40

4 Laloda (Fatehabad) 3.50 1.80

5 Gochi (Jhajjar) 1.00 0.60

6 Dabra (Hisar) 4.50 3.45

7 Satrod( Hisar) 4.00 3.25

8 Julani-Khera (Kaithal) 1.50 0.80

9 Mauli (Panchkula) 1.00 0.60

10 Majra (Jhajjar) 1.00 0.60

11 Gagan Kheri (Hisar) 1.60 1.20 

 

 

 Fresh Water Prawn Farming  

 

There are more than 100 species of Freshwater prawn found in the world. There are more than 25 species are found in India. Out of these 10 species are important from commercial point of view. Out of them Macrobrachium rosenbengii is the main species which is used in culture practices. This is also know as giant prawn. This can be cultured in both fresh water as well as brackish water. It is fast growing animal and farmers can culture profitably. It contains 20-22 percent animal protein and has less cholestrol. It has essential amino-acids and mineral which are very important for human beings. In culture

practices, the freshwater prawn has two stages i.e Nursery Pond and Growout Pond. Fresh water prawn is stocked in nursery pond for 45-60 days then it is shifted to grow-out ponds. The ponds are prepared by using manure and fertilizers. The stocking density in nursery pond is kept 2.00-2.50 lakh per hectare. Feed is provided 5 times @ 8-10 gm per kg body weight at initial stage. Check trays are used to regulate the feeding. Prawn crop becomes ready for sale with 7-8 months. The expenditure about Rs. 1.50 lakh per hectare and income is Rs. 2.50 lakh. Thus net income is Rs. 1.00 lakh per hectare in 8 months.

 

 

     

Economics of Prawn Culture (Per Hect.)a) Capital Investment Rs.

  Construction of Pond,Water Supply Channel, Installation of Tubewell/Renovation/Lease Amount

200000

     b) Recurring Expenditure Rs.

  Electricity & Diesel 10000  Cost of 250Kg Lime 750  20 KG Urea 160  50 KG Single Super Phosphate 250  Seed Cost of 50000 Seeds 27500  Artificial Feeding , Palleted Feed 2000 kg 44000  Vitamins, minerals & medicines 1000  Expenditure on marketing, harvesting and watch & wild 10000

EXPENDITURE 93660     

c) Economics  Expenditure on Capital Investment @16% 320000  Deprecation on Capital Investment @10% 20000  Recurring Expenditure 93660

  TOTAL EXPENDITURE 145660     

d) Income  Sale of 1000 kg Prawn @ Rs.250/- per kg 250000     

e) Net Income ( Income - Total Expenditure) 104340   Note:- Theabpve economics may change as per productivity of pond and market prices of the

PRAWN 

2ND PARTFresh Water Fish FarmingFRIDAY, 01 MAY 2009 00:00 AMBRISH JHA OPPORTUNITIES - AGRICULTURE & RURAL

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Fish culture is practiced in less than 30 percent of the total areas available. This has a potential to create huge job

opportunities, provided fish cultivation is done on a scientific basis

India is a large producer of inland fish, ranking next only to Japan.

With an abundance of freshwater resources, India has still not been able to tap even 30% of the potential area for

inland fish production. Many entrepreneurs have, however, chosen to take this occupation on commercial scale. This

is best manifested in Andhra Pradesh, which with 10,56,000 tons of inland fish production in 2007-08 ranked next

only to West Bengal, which is far more endowed with water resources. Andhra Pradesh has emerged among the

ranks encouraging farmers to form cooperatives to take up farming in ponds around Kolleru lake.

Both the central and state governments have come up with schemes to help the cause of the farmers.

Rate

Fish culture in ponds

Out of the total inland fish production of over 3.6

million metric tons, more than 60% is contributed

by fish culture in ponds and reservoirs. The

average productivity from ponds on the national

level is around 2,500 kg/ha/year, though in Andhra

Pradesh and Haryana it is more than 5,000

kg/ha/year, while in some other states like Bihar

and UP it is anywhere between 1,500 and 2,500

kg/ha/year. Fish culture is adopted by all kinds of

farmers – small and marginal ones, relatively

larger farmers and those who do it on commercial

scale. Sizes of ponds also depend on how affluent the farmers are. Ponds less than 100 square meters in area prove

unsustainable, while those above 1 hectare are expensive for small players. Many farmers in Tamil Nadu, for

instance, use ponds of sizes 30 feet by 30 feet to make their living. On the other hand, a water spread of anything

less than 10 hectares in Andhra Pradesh is treated as a pond.

Ponds can be perennial or seasonal. While

seasonal ponds can be used for short-term fish

culture, provided they retain water for at least four to

five months, perennial ponds are suited for fish

culture on a larger scale. Since water dries up in a

few months, seasonal ponds are easy to harvest

fish. Any perennial pond retaining water depth of 2

meters can be used for fish culture. Dr Gopinath

Sai, executive director (technical), National

Fisheries Development Board (NFDB), says a water

level of 3 to 4 feet is preferable, even in summer.

Fish farming can be practiced on scientific lines in

perennial ponds only, though seasonal ponds can be used to cultivate fry. Though different pond shapes are being

adopted by farmers, rectangular ponds are easier to work on, Sai points out. He says freshwater fish culture is a very

profitable business provided farmers take up this on scientific lines. Quality of soil, water, fish seed and fish food

needs to be of reasonably good quality to have better yields. The soil for ponds should be able to retain water, and

hence clayey soil is preferable. The water should not be acidic in nature, nor should it be highly alkaline. It should be

treated with appropriate quantity of lime. Provision for inlets and outlets should be made in ponds, as Sai and C

Ratnamachari, joint director, Inland Fisheries, Andhra Pradesh, says.

However, Ranjit, a fish farmer from Bihar, now into fish culture and retail trading in Delhi, says, “We do not know

about any inlets or outlets in our ponds but we manage a good catch despite that.”

Ponds are not the natural habitat of fish; it is rivers and canals. This makes it imperative for farmers to provide food

from outside and also create a desirable environment. Fish food is provided in the form of oil cakes and rice bran. But

to create conditions suitable for other organisms to grow inside ponds, fertilizers need to be applied. A combination of

organic and inorganic fertilizers is ideal, Ratnamachari says. Their application depends on the soil quality to a great

extent.

Economics of Fish Culture in Ponds (for 1ha, up to 1m excavation)

Items Amount (in Rs)

Fish Species Bred in Ponds

3.6 million metric tons - Annual produce of inland fish in India, 60 % - come from fish culture in ponds and reservoirs, 60 species - cultivated in different parts of India in ponds or reservoirs, 80% - contribution of carps from fish culture

Major species cultured in ponds

Indian major carps – rohu, catla and mrigalExotic carps – silver carp, grass carp, common carpCatfish – magur, ari, singhi.Tilapia – also known as kowai.Trout – golden mahseer, silver mahseer, silver grey mahseer and black mahseer.

A. Fixed costs

Excavation of one hectare land (10,000 cubic meter land to the depth of one meter @Rs 20/cubic meter

200000

Construction of inlet and outlet to ponds 40000

Equipment and gears 15000

Total fixed costs 255000

B. Recurring costs

Lime 500 kg @ Rs 7/kg 3500

Fingerlings 5,000 in number @ Rs 600 for every 1000 3000

Organic manure (cow dung) 15 tons @ Rs 400/ton 6000

Urea 330 kg @ Rs 7/kg 2310

Super phosphate 165 kg @ Rs 6/kg 990

Ammonium sulphate 63 kg @ Rs 6/kg 378

Mustard oil cake 1350 kg@Rs 12/kg 16200

Rice bran 1350 kg @ Rs 4/kg 5400

Insurance cost @ 4% of seed and fertilizers 1200

Miscellaneous including harvesting, security of ponds, etc. 8000

Total recurring cost 46978

Total cost 301978

Income

Production (from second year onwards ) (in kg) 3000

Sale price (per kg) 45

Total Income (from second year onwards) (in Rs) 135000

Net income for first seven years

Net Income in first year -301978

Net Income in second year 88022

Net Income in third year 88022

Net Income in fourth year 88022

Net Income in fifth year 88022

Net Income in sixth year 88022

Net Income in seventh year 88022

Source: Updated from NABARD

Rajat Sharma of Haryana Fisheries Department has a simple mathematics for fish farming, which he says is followed

by most fish farmers in the state. He says what is needed to produce for 1 kilogram of fish is 1 cubic meter water, 1

kilogram of organic manure, 100 grams of inorganic fertilizer, 1 kilogram of supplementary feed and three fish seeds.

Farmers, he says, should wait for one year for the fish to mature. According to his calculation, investment needed for

1 kilogram of fish is anywhere between Rs 15 and 25. The sale price of 1 kilogram of fish to wholesalers is anywhere

between Rs 40 and 50, ensuring more than double the income.

Being a state subject, the fisheries department also helps farmers get the right quality fingerlings. Private hatcheries

have also come up in several parts of the country and government schemes are also aiding this process. Fingerlings

must be free from disease because one infected fish may cause widespread damage. Polyculture in ponds is the

dominant production system in most parts of the country. Carps, both Indian and exotic, contribute to almost 80% of

the produce from ponds. Rohu, katla, mrigal and magur are the favorite pond fish varieties.

«  Start   P

3RD PARTFish farmingFrom Wikipedia, the free encyclopedia

Intensive koi aquaculture facility in Israel

Fish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming

involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases young

(juvenile) fish into the wild for recreational fishing or to supplement a species' natural numbers is generally

referred to as a fish hatchery. The most common fish species raised by fish farms

aresalmon, carp, tilapia, European seabass, catfish and cod.

There is an increasing demand for fish and fish protein, which has resulted in widespread overfishing in wild

fisheries. Fish farming offers fish marketers another source. However, farming carnivorous fish, such

as salmon, does not always reduce pressure on wild fisheries, since carnivorous farmed fish are usually

fed fishmeal and fish oil extracted from wild forage fish. In this way, the salmon can consume in weight more

wild fish than they weigh themselves. The global returns for fish farming recorded by the FAO in 2008 totalled

33.8 million tonnes worth about $US 60 billion.[1]

Contents

[hide]

1 Major categories of fish aquaculture

o 1.1 Extensive aquaculture

1.1.1 Sources

o 1.2 Intensive aquaculture

2 Specific types of fish farms

o 2.1 Cage system

o 2.2 Irrigation ditch or pond systems

2.2.1 Composite fish culture

o 2.3 Integrated recycling systems

o 2.4 Classic fry farming

3 Issues

o 3.1 Labeling

4 Indoor fish farming

5 Slaughter methods

o 5.1 Inhumane methods

o 5.2 More humane methods

6 Photo gallery

7 See also

8 Notes

9 References

10 External links

[edit]Major categories of fish aquaculture

There are two kinds of aquaculture: extensive aquaculture based on local photosynthetical production and

intensive aquaculture, in which the fish are fed with external food supply.

[edit]Extensive aquaculture

Aqua-Boy, a Norwegian live fish carrier used to service the Marine Harvest fish farms on the West coast of Scotland

Limiting for growth here is the available food supply by natural sources, commonly zooplankton feeding

on pelagic algae or benthic animals, such ascrustaceans and mollusks. Tilapia species filter feed directly

on phytoplankton, which makes higher production possible. The photosynthetic production can be increased

by fertilizing the pond water with artificial fertilizer mixtures, such as potash, phosphorus, nitrogen and micro-

elements. Because most fish arecarnivorous, they occupy a higher place in the trophic chain and therefore only

a tiny fraction of primary photosynthetic production (typically 1%) will be converted into harvest-able fish.

A second point of concern is the risk of algal blooms. When temperatures, nutrient supply and available

sunlight are optimal for algal growth, algae multiply their biomass at an exponential rate, eventually leading to

an exhaustion of available nutrients and a subsequent die-off. The decaying algal biomass will deplete the

oxygen in the pond water because it blocks out the sun and pollutes it with organic and inorganic solutes (such

as ammonium ions), which can (and frequently do) lead to massive loss of fish.

Another option is to use a wetland system such as that of Veta La Palma.

In order to tap all available food sources in the pond, the aquaculturist will choose fish species which occupy

different places in the pond ecosystem, e.g., a filter algae feeder such as tilapia, a benthicfeeder such

as carp or catfish and a zooplankton feeder (various carps) or submerged weeds feeder such as grass carp.

Despite these limitations significant fish farming industries use these methods. In the Czech

Republic thousands of natural and semi-natural ponds are harvested each year for trout and carp. The large

ponds around Trebon were built from around 1650 and are still in use.

[edit]Sources

Introduction to Aquaculture, college notes, Department of Aquaculture, Wageningen University

Aquaculture:

training manual,

second edition,

Donald R.

Swift, ISBN 0-

85238-194-8

[edit]Intensive aquaculture

In these kinds of

systems fish production

per unit of surface can

be increased at will, as

long as

sufficient oxygen, fresh

water and food are

provided. Because of

the requirement of

sufficient fresh water, a

massive water

purification system

must be integrated in

the fish farm. A clever

way to achieve this is

the combination

Optimal water parameters for cold- and warm-water fish in intensive aquaculture[2]

Acidity pH 6-9

Arsenic <440 µg/L

Alkalinity >20 mg/L (as CaCO3)

Aluminum <0.075 mg/L

Ammonia (non-ionized) <O.O2mg/L

Cadmium<0.0005 mg/L in soft water;<0.005 mg/L in hard water

Calcium >5 mg/L

Carbon dioxide <5-10 mg/L

Chloride >4.0 mg/L

Chlorine <0.003 mg/L

Copper<0.0006 mg/L in soft water;<0.03 mg/L in hard water

Gas supersaturation<100% total gas pressure(103% for salmonid eggs/fry)(102% for lake trout)

Hydrogen sulfide <0.003 mg/L

Iron <0.1 mg/L

Lead <0.02 mg/L

Mercury <0.0002 mg/L

Nitrate <1.0 mg/L

Nitrite <0.1 mg/L

Oxygen6 mg/L for coldwater fish4 mg/L for warmwater fish

Selenium <0.01 mg/L

Total dissolved solids <200mg/L

Total suspended solids <80 NTU over ambient levels

Zinc <0.005 mg/L

of hydroponic horticulture and water treatment, see below. The exception to this rule are cages which are

placed in a river or sea, which supplements the fish crop with sufficient oxygenated water.

Some environmentalists object to this practice.

Expressing eggs from a female rainbow trout

The cost of inputs per unit of fish weight is higher than in extensive farming, especially because of the high cost

of fish feed, which must contain a much higher level of protein (up to 60%) thancattle food and a

balanced amino acid composition as well. However, these higher protein level requirements are a consequence

of the higher food conversion efficiency (FCR—kg of feed per kg of animal produced) of aquatic animals. Fish

like salmon have FCR's in the range of 1.1 kg of feed per kg of salmon[citation needed] whereas chickens are in the

2.5 kg of feed per kg of chicken range. Fish don't have to stand up or keep warm and this eliminates a lot of

carbohydrates and fats in the diet, required to provide this energy. This frequently is offset by the lower land

costs and the higher productions which can be obtained due to the high level of input control.

Essential here is aeration of the water, as fish need a sufficient oxygen level for growth. This is achieved by

bubbling, cascade flow or aqueous oxygen. Catfish, Clarias spp. can breathe atmospheric air and can tolerate

much higher levels of pollutants than trout or salmon, which makes aeration and water purification less

necessary and makes Clarias species especially suited for intensive fish production. In some Clariasfarms

about 10% of the water volume can consist of fish biomass.

The risk of infections by parasites like fish lice, fungi (Saprolegnia spp.), intestinal worms (such

as nematodes or trematodes), bacteria (e.g.,Yersinia spp., Pseudomonas spp.), and protozoa (such

as Dinoflagellates) is similar to animal husbandry, especially at high population densities. However, animal

husbandry is a larger and more technologically mature area of human agriculture and better solutions to

pathogen problem exist. Intensive aquaculture does have to provide adequate water quality (oxygen, ammonia,

nitrite, etc.) levels to minimize stress, which makes the pathogen problem more difficult. This means, intensive

aquaculture requires tight monitoring and a high level of expertise of the fish farmer.

Controlling roes manually

Very high intensity recycle aquaculture systems (RAS), where there is control over all the production

parameters, are being used for high value species. By recycling the water, very little water is used per unit of

production. However, the process does have high capital and operating costs. The higher cost structures mean

that RAS is only economical for high value products like broodstock for egg production, fingerlings for net pen

aquaculture operations, sturgeon production, research animals and some special niche markets like live fish.[3][4]

Raising ornamental cold water fish (goldfish or koi), although theoretically much more profitable due to the

higher income per weight of fish produced, has never been successfully carried out until very recently. The

increased incidences of dangerous viral diseases of koi Carp, together with the high value of the fish has led to

initiatives in closed system koi breeding and growing in a number of countries. Today there are a few

commercially successful intensive koi growing facilities in the UK, Germany and Israel.

Some producers have adapted their intensive systems in an effort to provide consumers with fish that do not

carry dormant forms of viruses and diseases.

[edit]Specific types of fish farms

Within intensive and extensive aquaculture methods, there are numerous specific types of fish farms; each has

benefits and applications unique to its design.

[edit]Cage system

Giant gourami is often raised in cages in central Thailand

Fish cages are placed in lakes, bayous, ponds, rivers or oceans to contain and protect fish until they can be

harvested. The method is also called "off-shore cultivation[5]" when the cages are placed in the sea. They can

be constructed of a wide variety of components. Fish are stocked in cages, artificially fed, and harvested when

they reach market size. A few advantages of fish farming with cages are that many types of waters can be used

(rivers, lakes, filled quarries, etc.), many types of fish can be raised, and fish farming can co-exist with sport

fishing and other water uses. Cage farming of fishes in open seas is also gaining popularity. Concerns of

disease, poaching, poor water quality, etc., lead some to believe that in general, pond systems are easier to

manage and simpler to start. Also, past occurrences of cage-failures leading to escapes, have raised concern

regarding the culture of non-native fish species in open-water cages. Even though the cage-industry has made

numerous technological advances in cage construction in recent years, the concern for escapes remains valid.

Main article: Copper alloys in aquaculture

Recently, copper alloys have become important netting materials in aquaculture. Copper alloys

are antimicrobial, that is, they destroy bacteria, viruses, fungi,algae, and other microbes. In the marine

environment, the antimicrobial/algaecidal properties of copper alloys prevent biofouling, which can briefly be

described as the undesirable accumulation, adhesion, and growth

of microorganisms, plants, algae, tubeworms, barnacles, mollusks, and other organisms.[6]

The resistance of organism growth on copper alloy nets also provides a cleaner and healthier environment for

farmed fish to grow and thrive.

In addition to its antifouling benefits, copper netting has strong structural and corrosion-resistant properties in

marine environments.

Copper-zinc brass alloys are currently (2011) being deployed in commercial-scale aquaculture operations in

Asia, South America and the USA (Hawaii). Extensive research, including demonstrations and trials, are

currently being implemented on two other copper alloys: copper-nickel and copper-silicon. Each of these alloy

types has an inherent ability to reduce biofouling, cage waste, disease, and the need for antibiotics while

simultaneously maintaining water circulation and oxygen requirements. Other types of copper alloys are also

being considered for research and development in aquaculture operations.

[edit]Irrigation ditch or pond systems

These use irrigation ditches or farm ponds to raise fish. The basic requirement is to have a ditch or pond that

retains water, possibly with an above-ground irrigation system (many irrigation systems use buried pipes with

headers.) Using this method, one can store one's water allotment in ponds or ditches, usually lined with

bentonite clay. In small systems the fish are often fed commercial fish food, and their waste products can help

fertilize the fields. In larger ponds, the pond grows water plants and algae as fish food. Some of the most

successful ponds grow introduced strains of plants, as well as introduced strains of fish.

Control of water quality is crucial. Fertilizing, clarifying and pH control of the water can increase yields

substantially, as long as eutrophication is prevented and oxygen levels stay high.Yields can be low if the fish

grow ill from electrolyte stress.

[edit]Composite fish culture

The Composite fish culture system is a technology developed in India by the Indian Council of Agricultural

Research in the 1970s. In this system both local and imported fish species, a combination of five or six fish

species is used in a single fish pond. These species are selected so that they do not compete for food among

them having different types of food habitats.[7][8] As a result the food available in all the parts of the pond is

used. Fish used in this system include catla and silver carp which are surface feeders, rohu a column feeder

and mrigal and common carp which are bottom feeders. Other fish will also feed on the excreta of the common

carp and this helps contribute to the efficiency of the system which in optimal conditions will produce 3000–

6000 kg of fish per hectare per year.

[edit]Integrated recycling systems

One of the largest problems with freshwater aquaculture is that it can use a million gallons of water per acre

(about 1 m³ of water per m²) each year. Extended water purification systems allow for the reuse (recycling) of

local water.

The largest-scale pure fish farms use a system derived (admittedly much refined) from the New Alchemy

Institute in the 1970s. Basically, large plastic fish tanks are placed in a greenhouse. Ahydroponic bed is placed

near, above or between them. When tilapia are raised in the tanks, they are able to eat algae, which naturally

grows in the tanks when the tanks are properly fertilized.

The tank water is slowly circulated to the hydroponic beds where the tilapia waste feeds commercial plant

crops. Carefully cultured microorganisms in the hydroponic bed convert ammonia to nitrates, and the plants are

fertilized by the nitrates and phosphates. Other wastes are strained out by the hydroponic media, which

doubles as an aerated pebble-bed filter.

This system, properly tuned, produces more edible protein per unit area than any other. A wide variety of plants

can grow well in the hydroponic beds. Most growers concentrate on herbs (e.g. parsleyand basil), which

command premium prices in small quantities all year long. The most common customers

are restaurant wholesalers.

Since the system lives in a greenhouse, it adapts to almost all temperate climates, and may also adapt

to tropical climates. The main environmental impact is discharge of water that must be salted to maintain the

fishes' electrolyte balance. Current growers use a variety of proprietary tricks to keep fish healthy, reducing

their expenses for salt and waste water discharge permits. Some veterinary authorities speculate that

ultraviolet ozone disinfectant systems (widely used for ornamental fish) may play a prominent part in keeping

the Tilapia healthy with recirculated water.

A number of large, well-capitalized ventures in this area have failed. Managing both the biology and markets is

complicated.

Reference: Freshwater Aquaculture: A Handbook for Small Scale Fish Culture in North America, by William

McLarney

[edit]Classic fry farming

This is also called a "Flow through system" [9] Trout and other sport fish are often raised from eggs to fry or

fingerlings and then trucked to streams and released. Normally, the fry are raised in long, shallow concrete

tanks, fed with fresh stream water. The fry receive commercial fish food in pellets. While not as efficient as the

New Alchemists' method, it is also far simpler, and has been used for many years to stock streams with sport

fish. European eel (Anguilla anguilla) aquaculturalists procure a limited supply of glass eels, juvenile stages of

the European eel which swim north from theSargasso Sea breeding grounds, for their farms. The European eel

is threatened with extinction because of the excessive catch of glass eels by Spanish fishermen and

overfishing of adult eels in, e.g., the Dutch IJsselmeer, Netherlands. As per 2005, no one has managed to

breed the European eel in captivity.

[edit]Issues

See also: Aquaculture of salmon#Issues

The issue of feeds in fish farming has been a controversial one. Many cultured fishes (tilapia, carp, catfish,

many others) require no meat or fish products in their diets. Top-level carnivores (most salmon species)

depend on fish feed of which a portion is usually derived from wild caught (anchovies, menhaden, etc.).

Vegetable-derived proteins have successfully replaced fish meal in feeds for carnivorous fishes, but vegetable-

derived oils have not successfully been incorporated into the diets of carnivores.

Secondly, farmed fish are kept in concentrations never seen in the wild (e.g. 50,000 fish in a 2-acre (8,100 m2)

area.[10]) with each fish occupying less room than the average bathtub. This can cause several forms of

pollution. Packed tightly, fish rub against each other and the sides of their cages, damaging their fins and tails

and becoming sickened with various diseases and infections. This also causes stress.

However, fish tend also to be animals that aggregate into large schools at high density. Most successful

aquaculture species are schooling species, which do not have social problems at high density. Aquaculturists

tend to feel that operating a rearing system above its design capacity or above the social density limit of the fish

will result in decreased growth rate and increased FCR (food conversion ratio - kg dry feed/kg of fish

produced), which will result in increased cost and risk of health problems along with a decrease in profits.

Stressing the animals is not desirable, but the concept of and measurement of stress must be viewed from the

perspective of the animal using the scientific method.[11]

Sea lice, particularly Lepeophtheirus salmonis and various Caligus species, including Caligus

clemensi and Caligus rogercresseyi, can cause deadly infestations of both farm-grown and wild salmon.[12]

[13] Sea lice are ectoparasites which feed on mucus, blood, and skin, and migrate and latch onto the skin of wild

salmon during free-swimming, planktonic nauplii and copepodid larval stages, which can persist for several

days.[14][15][16] Large numbers of highly populated, open-net salmon farms can create exceptionally large

concentrations of sea lice; when exposed in river estuaries containing large numbers of open-net farms, many

young wild salmon are infected, and do not survive as a result.[17][18] Adult salmon may survive otherwise critical

numbers of sea lice, but small, thin-skinned juvenile salmon migrating to sea are highly vulnerable. On

the Pacific coast of Canada, the louse-induced mortality of pink salmon in some regions is commonly over

80%.[19]

A 2008 meta-analysis of available data shows that salmon farming reduces the survival of associated wild

salmon populations. This relationship has been shown to hold for Atlantic, steelhead, pink, chum, and coho

salmon. The decrease in survival or abundance often exceeds 50 percent. [20]

Diseases and parasites are the most commonly cited reasons for such decreases. Some species of sea

lice have been noted to target farmed coho and Atlantic salmon.[21] Such parasites have been shown to have an

effect on nearby wild fish. One place that has garnered international media attention is British

Columbia's Broughton Archipelago. There, juvenile wild salmon must "run a gauntlet" of large fish farms

located off-shore near river outlets before making their way to sea. It is alleged that the farms cause such

severe sea lice infestations that one study predicted in 2007 a 99% collapse in the wild salmon population by

2011.[22] This claim, however, has been criticized by numerous scientists who question the correlation between

increased fish farming and increases in sea lice infestation among wild salmon.[23]

Because of parasite problems, some aquaculture operators frequently use strong antibiotic drugs to keep the

fish alive (but many fish still die prematurely at rates of up to 30 percent[24]). In some cases, these drugs have

entered the environment. Additionally, the residual presence of these drugs in human food products has

become controversial. Use of antibiotics in food production is thought to increase the prevalence of antibiotic

resistance in human diseases.[25] At some facilities, the use of antibiotic drugs in aquaculture has decreased

considerably due to vaccinations and other techniques.[26] However, most fish farming operations still use

antibiotics, many of which escape into the surrounding environment.[27]

The lice and pathogen problems of the 1990s facilitated the development of current treatment methods for sea

lice and pathogens. These developments reduced the stress from parasite/pathogen problems. However, being

in an ocean environment, the transfer of disease organisms from the wild fish to the aquaculture fish is an ever-

present risk.[28]

The very large number of fish kept long-term in a single location contributes to habitat destruction of the nearby

areas. The high concentrations of fish produce a significant amount of condensed faeces, often contaminated

with drugs, which again affect local waterways. However, these effects are very local to the actual fish farm site

and are minimal to non-measurable in high current sites.

Concern remains that resultant bacterial growth strips the water of oxygen, reducing or killing off the local

marine life. Once an area has been so contaminated, the fish farms are moved to new, uncontaminated areas.

This practice has angered nearby fishermen.[29]

Other potential problems faced by aquaculturists are the obtaining of various permits and water-use rights,

profitability, concerns about invasive species and genetic engineering depending on what species are involved,

and interaction with the United Nations Convention on the Law of the Sea.

In regards to genetically modified farmed salmon, concern has been raised over their proven reproductive

advantage and how it could potentially decimate local fish populations, if released into the wild. Biologist Rick

Howard [30] did a controlled laboratory study where wild fish and GMO fish were allowed to breed. The GMO

fish crowded out the wild fish in spawning beds, but the offspring were less likely to survive. The colorant used

to make pen-raised salmon appear rosy like their wild cousins has been linked with retinal problems in humans.

[29]

[edit]Labeling

In 2005, Alaska passed legislation requiring that any genetically altered fish sold in the state be labeled.[31] In

2006, a Consumer Reports investigation revealed that farm-raised salmon is frequently sold as wild.[32]

In 2008, the US National Organic Standards Board allowed farmed fish to be labeled as organic provided less

than 25% of their feed came from wild fish. This decision was criticized by the advocacy group Food & Water

Watch as "bending the rules" about organic labeling.[33] In the European Union, fish labeling as to species,

method of production and origin, has been required since 2002.[34]

Concerns continue over the labeling of salmon as farmed or wild caught, as well as about the humane

treatment of farmed fish. The Marine Stewardship Council has established an Eco label to distinguish between

farmed and wild caught salmon,[35] while the RSPCA has established the Freedom Food label to indicate

humane treatment of farmed salmon as well as other food products.[34]

[edit]Indoor fish farming

An alternative to outdoor open ocean cage aquaculture, is through the use of a recirculation aquaculture

system (RAS). A RAS is a series of culture tanks and filters where water is continuously recycled and

monitored to keep optimal conditions year round. To prevent the deterioration of water quality, the water is

treated mechanically through the removal of particulate matter and biologically through the conversion of

harmful accumulated chemicals into nontoxic ones.

Other treatments such as UV sterilization, ozonation, and oxygen injection are also used to maintain optimal

water quality. Through this system, many of the environmental drawbacks of aquaculture are minimized

including escaped fish, water usage, and the introduction of pollutants. The practices also increased feed-use

efficiency growth by providing optimum water quality (Timmons et al., 2002; Piedrahita, 2003).

One of the drawbacks to recirculation aquaculture systems is water exchange. However, the rate of water

exchange can be reduced through aquaponics, such as the incorporation of hydroponically grown plants

(Corpron and Armstrong, 1983) and denitrification (Klas et al., 2006). Both methods reduce the amount of

nitrate in the water, and can potentially eliminate the need for water exchanges, closing the aquaculture system

from the environment. The amount of interaction between the aquaculture system and the environment can be

measured through the cumulative feed burden (CFB kg/M3), which measures the amount of feed that goes into

the RAS relative to the amount of water and waste discharged.

Because of its high capital and operating costs, RAS has generally been restricted to practices such as

broodstock maturation, larval rearing, fingerling production, research animal production, SPF (specific

pathogen free) animal production, and caviar and ornamental fish production. Although the use of RAS for

other species is considered by many aquaculturalists to be impractical, there has been some limited successful

implementation of this with high value product such as barramundi, sturgeon and live tilapia in the US.[36]

[edit]Slaughter methods

Tanks saturated with carbon dioxide have been used to make fish unconscious. Then their gills are cut with a

knife so that the fish bleed out before they are further processed. This is no longer considered a humane

method of slaughter. Methods that induce much less physiological stress are electrical or percussive stunning

and this has led to the phasing out of the carbon dioxide slaughter method in Europe.[37]

[edit]Inhumane methods

According to T. Håstein of the National Veterinary Institute, "Different methods for slaughter of fish are in place

and it is no doubt that many of them may be considered as appalling from an animal welfare point of view."[38] A

2004 report by the EFSA Scientific Panel on Animal Health and Welfare explained: "Many existing commercial

killing methods expose fish to substantial suffering over a prolonged period of time. For some species, existing

methods, whilst capable of killing fish humanely, are not doing so because operators don’t have the knowledge

to evaluate them."[39] Following are some of the less humane ways of killing fish.

Air Asphyxiation. This amounts to suffocation in the open air. The process can take upwards of 15 minutes

to induce death, although unconsciousness typically sets in sooner. [40]

Ice baths / chilling. Farmed fish are sometimes chilled on ice or submerged in near-freezing water. The

purpose is to dampen muscle movements by the fish and to delay the onset of post-death decay.

However, it does not necessarily reduce sensibility to pain; indeed, the chilling process has been shown to

elevate cortisol. In addition, reduced body temperature extends the time before fish lose consciousness. [41]

CO2 narcosis.

Exsanguination without stunning. This is a process in which fish are taken up from water, held still, and cut

so as to cause bleeding. According to references in Yue[42] , this can leave fish writhing for an average of

four minutes, and some catfish still responded to noxious stimuli after more than 15 minutes.

[edit]More humane methods

Percussive stunning.

Electric stunning. This can be humane when a proper current, duration, conductivity, and temperature are

present. One advantage is that in-water stunning allows fish to be rendered unconscious without stressful

handling or displacement.[43] However, improper stunning may not induce insensibility long enough to

prevent the fish from enduring exsanguination while conscious.[39] It's unknown whether the optimal

stunning parameters that researchers have determined in studies are used by the industry in practice.[43]

[edit]Photo gallery

Houseboat rafts with cages under for rearing fish. Near My Tho, Mekong delta, Vietnam.

 

Transport boats moored at fish processing plant. My Tho, Mekong delta, Vietnam.

 

Workers removing fish from hold of transport boat. My Tho, Mekong delta, Vietnam.

 

Fish reared in cages. My Tho, Mekong delta, Vietnam.

 

A communal Zapotec fish farm inIxtlán de Juárez, Oaxaca, Mexico.

[edit]See also

Agriculture and Agronomy portal

Aquaculture

Farm-raised catfish

Maine Salmon

Animal Slaughter

[edit]Notes

1. ^ Fishery and Aquaculture Statistics: Aquaculture Production2008 FAO Yearbook, Rome.

2. ^ Stress and Physiology By Dr. BiIl Krise at Bozeman Technology Center, and Dr. Gary Wedemeyer at

Western Fisheries Research Center. January 2002

3. ^ Weaver, D E (2006) Design and operations of fine media fluidized bed biofilters for meeting oligotrophic

water requirements Aquacultural Engineering 34(3): 303-310.

4. ^ Avnimelech Y, M Kochva, et al. (1994) Development of controlled intensive aquaculture systems with a

limited water exchange and adjusted carbon to nitrogen ratio. Israeli Journal of Aquaculture Bamidgeh

46(3): 119-131.

5. ^ Off-shore fish farming term

6. ^ http://en.wikipedia.org/wiki/Copper_alloys_in_aquaculture

7. ^ Strategy for transfer of composite fish culture technology

8. ^ Pond fish farming

9. ^ Flow-trough system term

10. ^ “Fuss Over Farming Fish”, Alaska Science Forum, June 27, 1990

11. ^ Journal of Fish Biology 68 (2): 332-372 February 2006

12. ^ Sea Lice and Salmon: Elevating the dialogue on the farmed-wild salmon story Watershed Watch Salmon

Society, 2004.

13. ^ Bravo, S. (2003). "Sea lice in Chilean salmon farms". Bull. Eur. Assoc. Fish Pathol. 23, 197–200.

14. ^ Morton, A., R. Routledge, C. Peet, and A. Ladwig. 2004 Sea lice (Lepeophtheirus salmonis) infection

rates on juvenile pink (Oncorhynchus gorbuscha) and chum (Oncorhynchus keta) salmon in the nearshore

marine environment of British Columbia, Canada. Canadian Journal of Fisheries and Aquatic Sciences

61:147–157.

15. ^ Peet, C. R. 2007. Thesis, University of Victoria.

16. ^ Krkošek, M., A. Gottesfeld, B. Proctor, D. Rolston, C. Carr-Harris, M.A. Lewis. 2007. Effects of host

migration, diversity, and aquaculture on disease threats to wild fish populations. Proceedings of the Royal

Society of London, Ser. B 274:3141-3149.

17. ^ Morton, A., R. Routledge, M. Krkošek. 2008. Sea louse infestation in wild juvenile salmon and Pacific

herring associated with fish farms off the east-central coast of Vancouver Island, British Columbia. North

American Journal of Fisheries Management 28:523-532.

18. ^ Krkošek, M., M.A. Lewis, A. Morton, L.N. Frazer, J.P. Volpe. 2006. Epizootics of wild fish induced by farm

fish. Proceedings of the National Academy of Sciences 103:15506-15510.

19. ^ Krkošek, Martin, et al. Report: "Declining Wild Salmon Populations in Relation to Parasites from Farm

Salmon",Science: Vol. 318. no. 5857, pp. 1772 - 1775, 14 December 2007.

20. ^ Ford JS and Myers RA (2008) [doi:10.1371/journal.pbio.0060033 "A Global Assessment of Salmon

Aquaculture Impacts on Wild Salmonids" PLoS Biol,6(2): e33.

21. ^ University of Maine, Department of Animal, Veterinary and Aquaculture Sciences, "Sea Lice Information".

22. ^ Fish Farms Drive Wild Salmon Populations Toward Extinction

23. ^ Northwest Fish Experts Debunk Controversial Sea Lice Study

24. ^ Lymbery, P. CIWF Trust report, "In Too Deep - The Welfare of Intensively Farmed Fish" (2002)

25. ^ Facts About Antibiotic Resistance

26. ^ UNH Aquaculture website

27. ^ Barrionuevo, Alexei (July 26, 2009). "Chile’s Antibiotics Use on Salmon Farms Dwarfs That of a Top

Rival’s". The New York Times. Retrieved 2009-08-28.

28. ^ Bulletin of the European Association of Fish Pathologists 22 (2): 117-125 2002

29. ^ a b Salmon Farming Tactics Produce Unhealthy Fish

30. ^ Purdue scientists: Genetically modified fish could damage ecology.

31. ^ "Alaska Passes Law Requiring Mandatory Labeling of Genetically Engineered Fish". Retrieved 29 June

2010.

32. ^ "Consumer Reports reveals that farm-raised salmon is often sold as "wild"". July 5, 2006. Retrieved 29

June 2010.

33. ^ Eilperin, Juliet; Black, Jane (November 20, 2008). "USDA Panel Approves First Rules For Labeling

Farmed Fish 'Organic'". The Washington Post. Retrieved 29 June 2010.

34. ^ a b "Environmental Labelling". Retrieved 29 June 2010.

35. ^ "MSC eco-label helps consumers identify certified wild Alaska salmon". January 15, 2004. Retrieved 29

June 2010.

36. ^ :[1] [2]  [3] [4] [5]

37. ^ Victoria Braithwaite (2010) Do fish feel pain?, Oxford University Press, p. 180

38. ^ Håstein 2004, pp. 224.

39. ^ a b European Food Safety Authority 2004, pp. 22.

40. ^ Benson, pp. 23.

41. ^ Yue, pp. 4.

42. ^ Yue, pp. 6.

43. ^ a b Yue, pp. 7.

[edit]References

Benson, Tess. "Advancing Aquaculture: Fish Welfare at Slaughter". Retrieved 2011-06-12.

Yue, Stephanie. "An HSUS Report: The Welfare of Farmed Fish at Slaughter". Humane Society of the

United States. Retrieved 2011-06-12.

"Opinion of the Scientific Panel on Animal Health and Welfare on a request from the Commission related

to welfare aspects of the main systems of stunning and killing the main commercial species of

animals". The EFSA Journal. 2004. Retrieved 2011-06-12.

Håstein, T (2004), "Animal welfare issues relating to aquaculture", Proceedings of the Global Conference

on Animal Welfare: an OIE Initiative, pp. 219–31, retrieved 2011-06-12

[edit]External links

Look up fish farm in

Wiktionary, the free

dictionary.

Wikimedia Commons has

media related to: Fish farming

AquacultureWorld: Aquaculture information

NOAA Aquaculture Website

FAO Fisheries Department and its SOFIA report on fisheries and aquaculture

Aquaculture Network Information Center (AquaNIC)

Brown, Lester R (2001) Fish Farming May Soon Overtake Cattle Ranching As a Food Source Earth Policy

Institute.

Watershed Watch Salmon Society A British Columbia advocacy group for wild salmon

Wild Salmon in Trouble: The Link Between Farmed Salmon, Sea Lice and Wild Salmon - Watershed

Watch Salmon Society. Animated short video based on peer-reviewed scientific research, with subject

background article Watching out for Wild Salmon.

Aquacultural Revolution: The scientific case for changing salmon farming - Watershed Watch Salmon

Society. Short video documentary. Prominent scientists and First Nation representatives speak their minds

about the salmon farming industry and the effects of sea lice infestations on wild salmon populations.

"The Case for Fish and Oyster Farming," Carl Marziali, University of Southern California Trojan Family

Magazine, May 17, 2009.

Norwegian fishfarming

Coastal Alliance for Aquaculture Reform Coalition of environmental groups, scientists and First Nations

opposed to current salmon farming practices

German Specialist in Fancy Goldfish and Fishhealth, with Forum and large Picture-Gallery

Fish farming facts from Greenpeace

Ethical concerns about the conditions on fish farms

Safety for Fish Farm Workers, from the U.S. National Agricultural Safety Database

The Pure Salmon Campaign website

Tropical Fish Farming in Florida

Nature's Subsidies to Shrimp and Salmon Farming

Fish Farming Business.com Start Up & Success Tips For Fish Farm Business Owners

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4TH PARTFish FarmingFish farming is the principal form of aquaculture, while other methods may fall under mariculture. It involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery. Fish species raised by fish farms include salmon, catfish, tilapia, cod, carp, trout and others.

Increasing demands on wild fisheries by commercial fishing operations have caused widespread overfishing. Fish farming offers an alternative solution to the increasing market demand for fish and fish protein.

Major categories of Fish FarmsBasically there are two kinds of aquaculture: extensive aquaculture based on local photosynthetical production and intensive aquaculture, in which the fish are fed with external food supply. The management of these two kinds of aquaculture systems are completely different.

Extensive (Pond) AquacultureLimiting for fish growth here is the available food supply by natural sources, commonly zooplankton feeding on pelagic algae or benthic animals, such as certain crustaceans and mollusks. Tilapia species filter feed directly on phytoplankton, which makes higher production possible. The photosynthetical production can be increased by fertilizing the pond water with artificial fertilizer mixtures, such as potash, phosphorus, nitrogen and microelements. Because most fish are carnivorous, they occupy a higher place in the trophic chain and therefore only a tiny fraction of primary photosynthetic production (typically 1%) will be converted into harvestable fish.

As a result, without additional feeding the fish harvest will not exceed 200 kilograms of fish per hectare per year, equivalent to 1% of the gross photosynthetic production.

A second point of concern is the risk of algal blooms. When temperatures, nutrient supply and available sunlight are optimal for algal growth, algae multiply their biomass at an exponential rate, eventually leading to an exhaustion of available nutrients and a

subsequent die-off. The decaying algal biomass will deplete the oxygen in the pond water and pollute it with organic and inorganic solvents (such as ammonium ions), which can (and frequently do) lead to massive loss of fish.

In order to tap all available food sources in the pond, the aquaculturist will choose fish species which occupy different places in the pond ecosystem, e.g., a filter algae feeder such as tilapia, a benthic feeder such as carp or catfish and a zooplankton feeder (various carps) or submerged weeds feeder such as grass carp.

Intensive (Closed-Circulation) AquacultureIn this kind of systems fish production per unit of surface can be increased at will, as long as sufficient oxygen, fresh water and food are provided. Because of the requirement of sufficient fresh water, a massive water purification system must be integrated in the fish farm. A clever way to achieve this is the combination of hydroponic horticulture and water treatment, see below. The exception to this rule are cages which are placed in a river or sea, which supplements the fish crop with sufficient fresh water. Environmentalists object to this practice.

The cost of inputs per unit of fish weight is higher than in extensive farming, especially because of the high cost of fish food, which must contain a much higher level of protein (up to 60%) than, e.g., cattle food and a balanced amino acid composition as well. This frequently is offset by the lower land costs and the higher productions which can be obtained due to the high level of input control.

Essential here is aeration of the water, as fish need a sufficient oxygen level for growth. This is achieved by bubbling, cascade flow or liquid oxygen. Catfish, Clarias ssp. can breathe atmospheric air and can tolerate much higher levels of pollutants than, e.g., trout or salmon, which makes aeration and water purification less necessary and makes Clarias species especially suited for intensive fish production. In some Clarias farms about 10% of the water volume can consist of fish biomass.

Especially when fish densities are high, the risk of infections by parasites like fish lice, fungi (Saprolegnia ssp.), intestinal worms (such as nematodes or trematodes), bacteria (e.g., Yersinia ssp, Pseudomonas ssp.), and protozoa (such as Dinoflagellates) is much higher than in animal husbandry because of the ease in which pathogens can invade the fish body (e.g. by the gills). The same holds for water pollution or depletion of oxygen in the water, which can ruin a fish crop within minutes. This means, intensive aquaculture requires tight monitoring and a high level of expertise of the fish farmer.

Intensive aquaculture was developed as a source for food fish. Raising ornamental cold water fish (goldfish or koi), although theoretically much more profitable due to the higher income per weight of fish produced, has never been successfully carried out till very recently. The increased incidences of dangerous viral diseases of koi Carp, together with the high value of the fish has led to initiatives in closed system koi breeding and growing in a number of countries. Today there are a few commercially successful intensive koi growing facilities in the UK, Germany and Israel.

Some producers have adapted their intensive systems and made them totally biosecure in an effort to provide consumers with fish that do not carry dormant forms of viruses and diseases.

Specific Types of Fish FarmsWithin intensive and extensive aquaculture methods there are numerous specific types of fish farms, each has benefits and applications unique to its design.

Integrated Recycling SystemsOne of the largest problems with freshwater aquaculture is that it can use a million gallons of water per acre (about 1 m³ of water per m²) each year. Extended water purification systems allow for the reuse (recycling) of local water.

The largest-scale pure fish farms use a system derived (admittedly much refined) from the New Alchemists in the 1970s. Basically, large plastic fish tanks are placed in a greenhouse. A hydroponic bed is placed near, above or between them. When tilapia are raised in the tanks, they are able to eat algae, which naturally grows in the tanks when the tanks are properly fertilized.

The tank water is slowly circulated to the hydroponic beds where the tilapia waste feeds a commercial plant crops. Carefully cultured microorganisms in the hydroponic bed convert ammonia to nitrates, and the plants are fertilized by the nitrates and phosphates. Other wastes are strained out by the hydroponic media, which doubles as an aerated pebble-bed filter.

This system, properly tuned, produces more edible protein per unit area than any other. A wide variety of plants can grow well in the hydroponic beds. Most growers concentrate on herbs (e.g. parsley and basil), which command premium prices in small quantities all year long. The most common customers are restaurant wholesalers.Since the system lives in a greenhouse, it adapts to almost all temperate climates, and may also adapt to tropical climates.

The main environmental impact is discharge of water that must be salted to maintain the fishes' electrolyte balance. Current growers use a variety of proprietary tricks to keep fish healthy, reducing their expenses for salt and waste water discharge permits. Some veterinary authorities speculate that ultraviolet ozone disinfectant systems (widely used for ornamental fish) may play a prominent part in keeping the Tilapia healthy with recirculated water.A number of large, well-capitalized ventures in this area have failed. Managing both the biology and markets is complicated.

Irrigation Ditch or Pond SystemsThese use irrigation ditches or farm ponds to raise fish. The basic requirement is to have a ditch or pond that retains water, possibly with an above-ground irrigation system (many irrigation systems use buried pipes with headers. Using this method, one can store one's water allotment in ponds or ditches, usually lined with bentonite clay. In small systems the fish are often fed commercial fish food, and their waste products can help fertilize the fields. In larger ponds, the pond grows water plants and algae as fish food. Some of the most successful ponds grow introduced strains of plants, as well as introduced strains of fish.

Control of water quality is crucial. Fertilizing, clarifying and pH control of the water can increase yields substantially, as long as eutrophication is prevented and oxygen levels stay high.Yields can be low if the fish grow ill from electrolyte stress.

Cage SystemFish cages are synthetic fiber cages kept in existing water resources to contain and protect fish until they can be harvested. A few advantages of fish farming with cages are that many types of water can be used (rivers, lakes, filled quarries, etc.), many types of fish can be raised, and fish farming can co-exist with sport fishing and other water uses. However, fish are vulnerable to disease, poaching, and low levels of dissolved oxygen. In general, pond systems are easier to manage, and simpler to start.

In regards to genetic modification of fish, cage systems can be detrimental to the environment because the genetically modified fish can easily escape into the wild destroying

other breeds of fish and upsetting the balance of nature.

Classic Fry FarmingTrout and other sport fish are often raised from eggs to fry or fingerlings and then trucked to streams and released. Normally, the fry are raised in long, shallow concrete tanks, fed with fresh stream water. The fry receive commercial fish food in pellets. While not as efficient as the New Alchemists' method, it is also far simpler, and has been used for many years to stock streams with sport fish. European eel (Anguilla anguilla) aquaculturalists procure a limited supply of glass eels, juvenile stages of the European eel which swim north from the Sargasso Sea breeding grounds, for their farms. The European eel is threatened with extinction because of the excessive catch of glass eels by Spanish fishermen and overfishing of adult eels in, e.g., the Dutch IJsselmeer, Netherlands. As per 2005, no one has managed to breed the European eel in captivity.

CriticismsThe issue of feeds in fish farming has been a controversial one. While vegetarian fish like tilapia require no meat products in their diets, carnivorous fish like salmon depend on fish feed of which a portion is usually derived from wild caught fish. Attempts to replace fish meal and oil in fish feed with vegetable sources of protein like soybeans are underway but have yet to be successful[citation needed].

Secondly, farmed fish are kept in concentrations never seen in the wild (e.g. 50,000 fish in a two-acre area) with each fish occupying less room than the average bathtub. This can cause several forms of pollution. Packed tightly, fish rub against each other and the sides of their cages, damaging their fins and tails and becoming sickened with various diseases and infections.

However, fish tend also to be animals that aggregate into large schools at high density. Most successful aquaculture species are schooling species, which do not have social problems at high density. Aquaculturists tend to feel that operating a rearing system above its design capacity or above the social density limit of the fish will result in decreased growth rate and FCR (food conversion ratio - kg dry feed/kg of fish produced), which will result in increased cost and risk of health problems along with a decrease in profits. Stressing the animals is not desirable, but the concept of and measurement of stress must be viewed from the perspective of the animal using the scientific method.

Some species of sea lice have been noted to target farmed coho and Atlantic salmon.Such parasites may have an effect on nearby wild fish. For these reasons, some aquaculture operators frequently use strong antibiotic drugs to keep the fish alive (but many fish still die prematurely at rates of up to 30%). In some cases, these drugs have entered the environment. Additionally, the residual presence of these drugs in human food products has become controversial.

The lice and pathogen problems of the 1990's facilitated the development of current treatment methods for sea lice and pathogens. These developments reduced the stress from parasite/pathogen problems. However, being in an ocean environment, the transfer of disease organisms from the wild fish to the aquaculture fish is an ever-present risk factor.

The very large number of fish kept long-term in a single location produces a significant amount of condensed feces, often contaminated with drugs, which again affect local waterways. However, these effects are very local to the actual fish farm site and are minimal to non-measurable in high current sites.

Other potential problems faced by aquaculturists are the obtaining of various permits and water-use rights, profitability, concerns about invasive species and genetic engineering

depending on what species are involved, and interaction with the UN Law of the Sea Treaty.

Environmentally Friendly MethodsAn alternative to open ocean cage aquaculture, one in which the the risk of environmental damage is substantially eliminated is through the use of a recirculating aquaculture system (RAS). A RAS is a series of culture tanks and filters where water is continuously recycled. To prevent the deterioration of water quality, the water is treated mechanically through the removal of particulate matter and biologically through the conversion of harmful accumulated chemicals into nontoxic ones.

Other treatments such as UV sterilization, ozonation, and oxygen injection are also utilized to maintain optimal water quality. Through this system, many of the environmental drawbacks of aquaculture are minimized including escaped fish, water usage, and the introduction of harmful pollutants. The practices also increase efficiency of feed utilisation and growth by providing optimal water quality parameters (Timmons et al., 2002; Piedrahita, 2003).

One of the drawbacks to recirculating aquaculture systems is water exchange. However, the rate of water exchange can be reduced through aquaponics, such as the incorporation of hydroponically grown plants (Corpron and Armstrong, 1983) and denitrification (Klas et al., 2006). Both methods reduce the amount of nitrate in the water, and can potentially eliminate the need for water exchanges, closing the aquaculture system from the environment. The amount of interaction between the aquaculture system and the environment can be measured through the cumulative feed burden (CFB kg/M3), which measures the amount of feed that goes into the RAS relative to the amount of water and waste discharged.

Because of its high capital and operating costs, RAS has generally been restricted to practices such as broodstock maturation, larval rearing, fingerling production, research animal production, SPF (specific pathogen free) animal production, and caviar and ornamental fish production. Although the use of RAS for other species is considered by many aquaculturalists to be impractical, there has been some limited successful implementation of this with with high value product such as barramundi, sturgeon and live tilapia in the US.

5TH PART

Ornamental Fish Farming

Ornamental fish keeping and its propagation has been an interesting activity for many, which provide

not only aesthetic pleasure but also financial openings. About 600 ornamental fish species have been

reported worldwide from various aquatic environments. Indian waters possess a rich diversity of

ornamental fish, with over 100indigenous varieties, in addition to a similar number of exotic species

that are bred incaptivity

Fish species/types suitable for breeding

Some tips for the successful production of ornamental fishes

Economics of small-scale breeding and rearing unit for live-bearers

Source: Central   In stitute of Freshwater Aquaculture, Bhubaneshwar, Orissa