Yellow Catfish Polyculture Technology: Efficient Micro-net Cage Farming Method
Setting up micro-net cages in ponds used for farming other aquatic species to raise yellow catfish is a high-yield farming method that increases water surface utilization, featuring simple operation, low investment, easy rearing, fast growth and high returns.
1 Net cage setup
The net cage is sewn from polyethylene netting, 2 m long, 2 m wide and 1.2 m high, with a mesh size of 0.5-1 cm. The cage uses a closed stretcher floating-fixed type, with a 9-mesh net cloth as a cushion layer at the bottom, the cushion layer edge being 20 cm high, to reduce feed loss; the upper part of the cage rises about 30 cm above the water surface. A square plastic basket made of 18-mesh polyethylene window screening, 10 cm high with a side length of 30 cm, is used as a feeding platform, placed in the middle of the cage body, one per cage. The net cages are set up at the water inlet of the fish pond, with 3-5 cages per mu (667 sq m) of pond. The cages can also be set up in spacious waters with fresh water quality, sufficient dissolved oxygen, shelter from wind and sun, and no pollution, arranged in a straight line, with a cage spacing of 4 m and a row spacing of about 10 m. Water hyacinth or alligator weed is transplanted inside the cage to cover about 2/3 of the cage area.
2 Fingerling stocking
The net cages are put into the water 1-2 weeks before fingerling stocking. The fingerlings are required to be disease-free, injury-free, robust and uniform in size. Stock 100-150 large-size yellow catfish fingerlings of about 20 g each per sq m.
3 Feeding management
3.1 Feeding
Common feeds include small trash fish, snail and clam meat, @#@254@#@, silkworm pupae, livestock and poultry viscera and animal blood. Feed at fixed times, fixed locations, with fixed quality and fixed quantity, ensuring the yellow catfish eat their fill and eat well and grow quickly.
3.2 Water management
Keep the water quality fresh and dissolved oxygen sufficient. Observe the fish activity every day and check whether the net cage is damaged, remove sick and dead fish from the cage, and keep the water body inside the cage clean. Clean the net cage once a week to ensure normal exchange of water inside and outside the cage. Adjust the height of the net cage promptly when the water level changes.
4 Disease control
Soak the net cage in bleaching powder solution for 30 minutes before putting it into the water; before the fingerlings are put into the cage, soak the fish bodies in salt solution to kill surface pathogens and parasites; every 10-15 days, splash lime water over the whole cage for disinfection once; regularly hang bags of copper sulfate and ferrous sulfate mixture; about every 20 days, make medicated feed with antibiotics and feed continuously for 2-3 days.