Efficient culture technology of golden trout in pond running water

Golden trout is a golden strain selected from rainbow trout mutants in Japan. After it was introduced to China in 1996, it was named "golden trout" according to its color characteristics. Golden trout is a cold water fish, the upper water temperature of normal growth is 22 ℃, there is no obvious lower limit, the lower limit of water temperature close to 0 ℃ can still eat a small amount and survive normally. It has delicious meat, rich nutrition, less thorns, more meat and high edible value. it is an excellent variety of ornamental, fishing and delicious food, and has become the second important breeding variety after rainbow trout in China. Golden trout can be cultured not only in ponds, but also in reservoirs, lakes and rivers, especially in running water in ponds. It can grow all the year round, and the yield per mu can be as high as 10,000 kg ~ 20,000 kg. Now the efficient culture technology of running water in golden trout pond is introduced as follows: first, pond construction. Mountain streams, springs, groundwater, reservoir bottom drainage, etc., can be used as water supply sources for golden trout pond culture. The water temperature of this kind of water source is generally above 0 ℃ in winter and 22 ℃ in summer, the dissolved oxygen in water is more than 6 mg / L, and the pH value is between 6.5 and 8, which meets the water standard for golden trout culture. Pond construction is based on the premise of no leakage and smooth flow. The terrain should have a certain slope to facilitate entry and drainage, and the drop of water is conducive to the natural increase of oxygen. Each pond area is generally 100 square meters ~ 200 square meters, cement structure, rectangular, conducive to feeding, management and control of fish disease, and can make water flow evenly to all parts of the pond. There are two forms of the inlet and outlet of the pond: one is equal to the width of the pond, and the whole section of the gate is over water from top to bottom, which is suitable for fish farms with large amount of water; the other is that the width of the inlet is only about 1 inch of the width of the pond, and the width of the outlet is 1 inch 2 of the width of the pond. At the same time, in order to prevent wild miscellaneous fish from entering the pond and escaping, fish bars should be set up at the inlet and outlet. Trout ponds are arranged in parallel and in series, but the series type is better, which is convenient and labor-saving. Second, the release of fish species. The fish species should be neat in specification, agile in swimming, strong in physique, bright golden in color. The stocking density of fish species is restricted by the amount of water, water temperature and the status of dissolved oxygen in the water, and the stocking quantity is proportional to the yield of adult fish within the range of feeding conditions. The specification of stocking depends on the breeding time, water temperature and planned listing specifications, generally between 80 grams and 100 grams per tail. Practice has proved that the water supply is 40 ~ 300 liters per second (the higher the temperature is, the greater the water supply is), 150 ~ 200 golden trout species can be released per square meter (the larger the specification is, the smaller the stocking density is). Before stocking, the pond should be fully exposed and thoroughly sterilized with quicklime or bleach; fish should be sterilized with 2%-3% salt solution before restocking, and it is best to avoid high temperatures at noon. Third, feed. At the initial stage of fish stocking, wild miscellaneous fish and livers of livestock and poultry can be ground into paste with a meat grinder for 2 ~ 3 times, put on a fine wire plate and hung in water. The daily feeding amount accounts for 6% ~ 8% of the fish body weight, 3 times a day, and then gradually feed artificial feed, feed ratio: animal and plant feed each accounts for 50%. Animal feed has fish meal, meat meal, small miscellaneous fish, silkworm pupa and livestock and poultry viscera, plant feed has cake powder, wheat bran, rice bran, vegetable leaves, etc., the particle size is palatable, the general diameter is 4 mm ~ 6 mm. Feed twice a day, using the method of hand sprinkling, the amount of feeding is 2%-3% of the total fish. Can be controlled flexibly according to the weather, water temperature and the appetite of fish, do not feed too much, so as not to pollute the water quality. Fourth, daily management. The water for golden trout culture must be clean and pollution-free. The bottom and wall of the fish pond should be cleaned regularly, and it is best to set up a fish fence 2 ~ 3 meters away from the outlet so that the dirt can precipitate, and then suck away with a straw to reduce pollution to the lower pond. In order to achieve high yield of golden trout, it is necessary to maintain sufficient water volume and sufficient dissolved oxygen content in management, so it is necessary to add oxygen-increasing equipment in the fish pond and replenish it immediately in case of hypoxia. Secondly, the adult fish that have reached the edible standard (tail weight more than 200 grams) should be caught and sold in time, and the individuals with obvious differences in growth should be selected and raised in separate ponds. Fifth, disease prevention and treatment. The first common disease in running water culture of golden trout is vibrio disease, which occurs in late spring and autumn. At the initial stage of the disease, the base of the body surface and fins gradually blackened, and in severe cases, the epidermis ruptured, exposing necrotic muscles. Prevention and treatment: 75 mg ~ 100 mg of sulfonamides per kilogram of fish body weight, fully mixed with feed, continuous feeding for 5 ~ 7 days. Second, liver steatosis venereal disease, this disease is due to the feed nutrition content is incomplete or mildew deterioration and so on. The diseased fish has black body color and enlarged liver. It floats in the slow flow place alone and is not lively. Prevention and treatment: it is found that diseased fish are immediately fed with high-quality feed, reduce the amount of feed, and increase the content of vitamins in the feed. The milder fish can fully recover after about 30 days, while the seriously ill cannot be saved.