Technical Points and Methods for Cage Culture of Catfish Explained

Cage culture of catfish, adult fish yield of 17.5 kg per sq m, economic benefit is 5-10 times that of grass carp and common carp. The main techniques are as follows:

1. Setting up cages, graded rearing

Select streams, rivers, lakes, reservoirs and other wide waters with clean water quality, high dissolved oxygen, and suitable pH to set up cages. Determine the mesh size and cage area according to the different growth stages of the river catfish. For fry cages, mesh 0.8-1 cm, area 8 sq m; for fingerling cages, mesh 1.5-2 cm, area 12-14 sq m; for adult fish cages, mesh 3 cm, length × width × height of 5 m × 5 m × 2.5 m. Generally, closed cages are used, with a water entry depth of 2 m.

Catfish mostly cannibalize each other during the larval stage, so timely screening and transferring to different cages for rearing is the key to improving the survival rate of river catfish. When the fish body reaches 10 cm in length, transfer them to fingerling cages for rearing, and when the body reaches 16.5 cm in length, transfer them to adult fish cages for culture.

2. Scientific feed formulation, “four fixed” feeding

When the fry have just entered the cages, feed them sufficient live bait such as tubifex so that they gradually adapt to the cage environment. When the fingerlings reach 5-7 cm, begin feeding finely processed feed with 10-15% fresh fish paste added to lure and train them to eat. In addition to the necessary nutrients, artificial compound feed should also have 1-2% mineral and vitamin additives added. The crude protein content of the feed is 50% in the early stage, 45% in the middle stage, and 40% in the late stage. Fish meal, soybean meal, wheat, corn, blood meal, silkworm pupa meal, etc. can be used for feeding, 3-5 times a day. River catfish have a habit of feeding at night, so special attention should be paid to increasing feeding at 11-12 p.m. When the fish body length is 10-16 cm, the feeding amount is 6-10% of the total weight of the fingerlings; when the body length is above 16 cm, it is 3-5%. Feeding should be fixed in time, location, quality, and quantity.

3. Strengthening management, preventing and treating fish diseases

Release the fry into the cages as early as possible. After entering the cages, check the cages regularly to prevent escape and theft. Clean the cages regularly, remove dirt, and ensure smooth exchange of water inside and outside. Observe the fish's feeding and growth conditions every day. Measure the growth rate regularly. Strengthen fish disease prevention and treatment. Before the body length reaches 16 cm, insist on splashing the cages with 10 ppm quicklime water 1-2 times every 5-10 days; after the body length reaches 16 cm, splash with 15 ppm quicklime water 1-2 times a month. In the first few days after the fry and fingerlings enter the cages, 0.5-1% garlic must be mixed into the feed every day. After that, use medicine once every 10-20 days until the fry body length reaches 16 cm, then change to using medicine once every 1-2 months.