Pisciculture

Pisciculture

Pisciculture or Fish culture is the process of breeding and rearing of fishes in ponds, reservoirs (dams), lakes, rivers and paddy fields. It is the farming of economically important fishes under controlled conditions. Pisciculture helps in integrated rural development by generating employment and income to fishing community and fish farmers.

1. Types of fish culture practices

a)        Extensive fish culture: Culture of fishes in large areas with low stocking density and natural feeding.

b)       Intensive fish culture: Culture of fishes in small areas with high stocking density and providing artificial feed to increase production.

c)        Pond culture: Rearing of fishes in pond water.

d)       Riverine fish culture: Rearing of fishes in lotic water.

e)        Dam culture (Culture in Reservoir): Culture of fishes in artificial man made constructed reservoirs.

f)         Lake culture (Culture in Lake): Rearing of fishes in lakes which are natural standing water bodies.

g)        Monoculture: Culture of single type of fish in a water body. It is also called mono species culture.

h)       Polyculture: Culture of more than one type of fish in a water body. It is also called composite fish culture.

i)          Integrated fish farming: It is the culture of fishes along with agricultural crops or

j)          animal husbandry farming. Rearing of fish along with paddy, poultry, cattle, pig and ducks.

2. Types of ponds for fish culture

Fish farm requires different types of pond for the various developmental stages of fish growth. They are:

a)        Breeding pond: Healthy and sexually mature male and female fishes are collected and introduced in this pond for breeding. The eggs released by the female are fertilized by the sperm and fertilized eggs float in water as frothy mass.

b)       Hatchling pits: The fertilized eggs are transferred to hatching pits for hatching. Two types of hatching pits are hatcheries and hatching hapas.

c)        Nursery ponds: The hatchlings are transferred from hatching pits after 2 to 7 days. The hatchlings grow into fry and are cultured in these ponds for about 60 days with proper feeding till they reach 2 - 2.5 cm in length.

d)       Rearing ponds: Rearing ponds are used to culture the fry. The fish fry are transferred from nursery pond to rearing ponds and are maintained for about three months till they reach 10 to 15 cm in length. In these rearing ponds the fry develops into fingerlings.

e)        Stocking pond: The stocking pond is also called as culture pond or production pond. These ponds are used to rear fingerlings upto the marketable size. Before releasing the fingerlings, the pond is manured with organic manure and inorganic fertilizers.

3. Cultivable food fishes in India

Freshwater cultivable fishes: Indian major carps (Kendai) – Catla, Rohu, Mrigal, catfishes (Keluthi), Murrels (Veral) and Tilapia (Jilebi kendai) are cultured in freshwater.

Marine water cultivable fishes: Sea bass (Koduva), Grey mullet (Madavai) and Chanos chanos (Milk fish) are the fishes cultured in marine water.

4.  Nutritional value of fishes

Cultivable freshwater and marine food fishes are highly nutritious, rich source of animal proteins and are easily digestible. They are rich in essential amino acids such as lysine and methionine, minerals like calcium, phosphorus, iron, sodium, potassium and magnesium. Fat soluble vitamins A, D and water soluble B-complex vitamins like pyridoxine, cyanocobalamine and niacin are found in fishes. Polyunsaturated fatty acid (PUFA) which are helpful in regulation of cholesterol are present in plenty in fishes and thus promote cardiac health.

5.  Fishery by-products

In addition to providing food, most of the fishing industries yield a number of by-products of commercial importance. These processed byproducts are used for human consumption and also for other purposes. These include:

a. Fish oil: It comprises of liver oil and body oil.

Liver oil of Cod, Tuna, Halibut and Shark are of great medicinal value and are rich in vitamin A, D and E.

Body oil is extracted from Sardines, Herrings, Salmons, Mackerels and Anchovies. They are used in industries for the preparation of lubricants, paints, varnishes and cosmetics.

b.  Fish Meal

It is prepared from the wastes of fish oil or from whole fish and contains nutritents like protein, fat, minerals and vitamins. It is used as feed for cattle and poultry farming animals.

Other by-products obtained from fishing industry are fish flour, fish manure, fish silage, fish guano, fish sausage, fish glue, fish leather and isinglass.