Culture of adult black fish

Black fish is a valuable freshwater fish with high economic value, which is called "the treasure of fish". It is very nutritious and contains a lot of protein, which is higher than that of chicken and beef. From the point of view of nutrition, black fish is a kind of advanced health food with comprehensive nutrition and delicious meat.

Black fish adult fish culture refers to the production process of cultivating fish species into edible fish in small water bodies such as ponds, ponds, cages and so on. There are two kinds of artificially cultured black fish: extensive mixed culture and intensive monoculture. Extensive mixed culture refers to mixed culture with four fish and other fish in fishing ponds. Intensive monoculture is the use of rich water and sufficient bait conditions for high-density monoculture, which is divided into cage monoculture and pond monoculture, mainly in ponds in recent years. Now briefly described as follows, for reference only.

Pre-culture preparation

1. Aquaculture facilities: soil ponds, cement ponds, etc. The depth of the water is 1 ~ 2 meters. The water supply and drainage facilities are complete.

two。 Water quality: no pollution is required, and the water quality should be neutral or weakly alkaline.

3. Area: the area of the fishing pond should be smaller, preferably about 1 mu, and the maximum should not exceed 2 mu.

4. Anti-escape facilities such as 40 cm ~ 60 cm fence shall be set up around the pool.

5. Plant water grass on the water surface around the pool, generally not more than 20% is appropriate, easy to block the sun, summer, prey, but also can purify water quality and adjust water temperature.

Culture technology

1. Fish stocking: ① fish species specifications of more than 10 cm of the current year, fish species should be the same specifications, no injury and no disease. The best source of ② fingerling is locally produced fish. The best stocking time for ③ is from early September to early October. Fish can be fed to restore their physique and improve the survival rate of overwintering. It will be released from March to April after 20 years. ④ disinfection: must be strictly sterilized before going into the pond. ⑤ stocking density: water depth 1.2m ~ 1.5m, 50g ~ 60g fish fry 8000 ~ 9000 fish per mu, 80g ~ 100g fish stocking 5000 ~ 6000 fish per mu.

two。 Feeding management: bait should adhere to the "four fixed", that is, fixed quality, quantitative, timing, positioning. Before feeding, the clapping sound is used as a "signal" to form a "sensory" response, and the black fish are gathered around the food field, which is easy to form a feeding situation, increase food intake and reduce bait waste.

The main food species are fresh aquatic animals, mainly sea and fresh water fish, shrimp and so on. When eating vigorously, the amount of bait is about 8% of the fish weight, and the high one can reach more than 10%. It is 3% or 4% in the off-season. When feeding, the "slow, fast and slow" method is adopted, which has a good feeding effect and less feed waste, and most of the fish can stop feeding after they are full. When the weather, air pressure and water quality are different, the food intake of fish is very different.

3. Daily management: mainly do the following aspects: ① pond patrol. Observe the feeding, activity and water quality changes of fish, whether there are signs of floating head, sick fish and so on. Problems should be dealt with in a timely manner. ②, change the water. Black fish eat high-protein diet every day, the concentration of ammonia in the pond water is high, especially the summer water temperature is high, the water is easy to deteriorate. For this reason, it is necessary to change the water body in time, which is usually replaced by 1 beat 3 a week and 4 beat 5 in half a month. Where there are conditions, it is best to maintain micro-running water culture, and the water temperature during the culture period should not be higher than 30 ℃. ③ anti-escape. As the black fish grows up gradually, the jumping ability is enhanced, especially when the water is changed in rainy days or in the early morning, so the height of the pool ridge from the water surface should generally be more than 50 centimeters, and a strong anti-escape net should be installed at the outlet. Anti-escape net or anti-escape wall is installed around the pool.

Disease and prevention

1. Water mildew. Prevention and control methods, in the net transport and stocking operation should be careful to prevent fish injury. When fish get sick, they can be washed with a saline solution of 3% to 5% concentration.

two。 Myxosporidiosis. The method of prevention and treatment was treated with 90% crystal trichlorfon with 0.2ppm~0.5ppm concentration.