INTRODUCTION 

Fish is a staple food for 80 % population of the State.  Out of which 63.51 % prefer freshwater fish and 33.22 % prefer marine fish.  Only 3.27 % are fond of Braekishwater fish.  The per capita annual consumption of fish in the State is 7.33 kg, mainly because of decline in total inland fish catch.  Although, impart of freshwater fish from the neighboring States continues to meet the increased consumers demand.

Suitable technology for freshwater pond fish culture which known as composite fish culture is now standardized.  This technology has been developed with a view to give benefit to all sections of people.  In other wards, the technology can be applied either as low cost, medium cost or high cost technology thereby people of different economic levels can adopt the technology depending on their financial ability.

PREPARATION OF POND

            Perennial ponds that retain water throughout the year to a minimum depth of 3’ are suitable.  The present village ponds/tanks are chocked with waterweeds. For fish culture, the waterweeds had to be removed from the ponds/tanks either with weedicides on manually.  After removed of the weeds, the pond should be free from predator fished by dissolving Mohua Oil Cake  @ 80 kg/Ac.  After this, the tank is fertilized with both organic and inorganic fertilizers.  If the Mouha Oil Cake is not available, then the raw Cow Dung @ 5,000 kg/Ac. is to be applied in the Pond/Tank.  For good production, the pond water should have PH ranging between 7.5 – 8.00.  In order to have this, lime will be applied in the tank @ 200 kg/Ac. per annum.  The lime should be applied after 15 days of application of Mohua Oil Cake.  The lime also helps in the eradication of any fish parasites existing in the tank and enables proper reaction of fertilizers.  The organic fertilizer i.e. Raw Cow Dung is dissolved in the tank @ 500 kg/Ac. Per annum.  This is followed by application of inorganic fertilizers like Super Phosphate @ 120 kg/Ac.  And Ammonium Sulphate @ 200 kg/Ac.  Generally the inorganic fertilizers are added to tank in installments throughout the culture period.  When the tank is fertilized in this manner, it develops proper Natural food of the fish i.e. Plankton.  The inorganic fertilizers are to be applied after 3 or 4 days of application of Raw Cow Dung.  Now the pond is ready for stocking.

STOCKING OF FISH SEEDS      

            After 15 days of application of inorganic fertilizers, the seed should be stocked. Now the tank is stocked with seed of different species ranging between 5 – 6 cms. @ 2000 per acre.  In composite fish culture six species combination is employed.  The species are Indian Major Carps, like Catla, Rohu, Mrigal and exotic Carps like Silver Carps, rass Carp and common Carp.  The ratio of stocking so six species should be 10:40:15:10:10:15 (C:R:M:SC:C:CC).

FEEDING

            The fish seed i.e. fry start feeding on the natural food in the water by occupying different ecological zones of the tank.  However, Natural food alone is not sufficient to achieve the expected production.  Hence, supplementary feeds like Groundnut Oil cake and Rice Bran are fed to the fishes during the culture.  Under this high cost technology the total quantity of the fish feed required is 1200 kg/Ac.  Per Annum. The supplementary feed is to be fed in 1:1 ratio.  By applying this technology, at the end of the culture period say 12 months, the fish will reach marketable size and fetch attractive prices.  A production of 1:2 tone per Acre or 3 tons per hectors can be assured under this technology.

            Under medium & low cost technologies, inputs are reduced correspondingly and hence the output/production will be lower. For implementation of this technology, there are certain constraints specially seed availability. The Carp Seed are collected from the rivers.  But when the technology of this type is followed, depending on river seed will upset the programme. Unfortunately, the Carp don’t naturally breed in the tanks.  They breed in the rivers when the floods occur during the monsoon . 

            In addition to fish culture, Poly culture of M. Rosenberg (giant fresh water prawn) or M. Malcomsonii is intended to be carried out alongwith Carps culture.  Separate pond preparation is not required.  Ponds are normally prepared under pre-stocking management for Carp culture.  The only addition is to stock additional quality of freshwater prawn seed with a view to generate additional income to the farmers from additional production of freshwater prawn.

            The desirable density for Poly culture of M. Rosenberg or M. Malcomsonii with Carps would be 10,000 per Acre.  Stocking of prawn seed and Carp seed may be done simultaneously.  The freshwater prawns being detritus feeder at the bottom, often consumes the droppings of Carps directly in addition to the available benthic food.  In this consideration, the composition of bottom feeder Carps should desirably be reduced.  Therefore, the rational composition of Carps for poly culture with freshwater prawns may be as under.

1.      Catla      :      40%

2.      Rohu      :      50%

3.      Mrigal      :      07%

 4.      Grass Carp :   03%

Where grass Carp is not available, Mrigal may be socked at 10%.  Common Crap may be avoided.  Stocking Minor quantity of grass Carp would detritus food for the prawn 

The conventional supplementary feed usually given to the Carps would be given daily in little excess.  So that, a part of that food can also be consumed by Prawns.  Besides, the conventional Carp feed i.e. fresh or boiled snail or bivalve meat of trash fish meat should be given exclusively for prawn.  It is always desirable to give more snail or bivalve meat if locally available in plenty.  The daily ration of feed requirement from 1 –7 months would be 0.25, 0.90, 2.1, 2.8, 3.35, 3.80, 3.90 kg. respectively .    

The desirable size at harvest should be around 70 grams and above.  These are applicable for all the schemes.

ECONOMICS FISH CULTURE:  Operational cost for 1-acre tank.

     ITEMS                      REQUIREMENT/RATE (RS.)            TOTALCOST (RS.)

1.      Lime                       :      200 kg./ 5.00 per kg.             :      1,000.00

2.      Raw Cow Dung                :      5, 000 kg./ 0.20 per kg      :       1,000.00

3.      Super Phosphate        :      25 kg./ 6.00 per kg.       :              150.00

4.      Ammonium Sulphate      :      25 kg./ 6.00 per kg.       :              150.00

5.      Fish Seed (2000Nos.)      :                 90.00 per thousand      :              180.00

6.      Prawn Seed (10,000 Nos.):               100.00 per thousand      :      1,000.00

7.      Rice Polish       :      600 kg./5.00 per kg.             :              300.00

8.      Groundnut Oil Cake      :      600 kg./10.00 per kg.             :           6,000.00   

9.      Trash Fish              :      225 kg./5.00 per kg.             :           1,125.00

10.  Horticulture            :      Rs. 500.00 per Ac.       :              500.00

11.  Contingency          :      Rs. 175.00 per Acre                 :              175.00

 INCOME:

 

1.      Fish production 1000 kg./Ac      35.00 per kg.                   :         35,000.00

2.      Prawn production 150 kg./Ac.    100.00 per kg.                         :         15,000.00

TOTAL.        50,000.00 

Net Profit:    35,720.00

FISH DISEASES AND ITS CONTROL

      Large-scale mortality of fish often occurs in ponds/tanks due to environmental stress followed by parasitic afflictions and bacterial, viral, fungal and protozoan infections etc.  Infestations are more liable to occur in ponds that are heavily stocked since such congestion provides a favorable situation for rapid spread of infection among the fish .

      The fish diseases may be classified as follows:  

1.        Parasitic Infection          : Caused by Fungi, Bacteria, Protozoa,

                                                  Worms & Crustaceans.

2.    Non-Parasitic Infection       :       Asphyxiation (Gas Disease)& Miscs .

DISEASES                                               
 1.      Fungus Infection      

2.      Bacterial Disease