Culture technique of Paralichthys olivaceus, fresh in Sea in Pond

Japanese flounder (Paralichthys olivaceae), commonly known as flounder, partial mouth and flounder in China, is not only a valuable marine fish, but also one of the important marine fish. Its individual is huge, the meat is delicate and delicious, it is a good material for making sashimi, deeply loved by consumers, the market is very broad, and the economic value is very high.

The following is a brief introduction to the culture techniques of Paralichthys olivaceus.

The culture site of Paralichthys olivaceus should be in the place where the water source is fresh, pollution-free, water exchange is convenient, power supply is guaranteed and transportation is convenient. Masonry walls can be used in the nurturance workshop, steel frame and wood frame structure are used on the roof, and glass tiles or asbestos tiles are covered to control the light, because excessive light will make the flounder uneasy, and algae will grow on the bottom and wall of the pond, thus affecting the feeding and growth of fish. The shape of the cement pool is rectangular, square, octagonal, etc., with an area of 30 square meters to 80 square meters, a water depth of 1 meter to 1.2 meters, an inclination of 2% to 3% in the direction of the outlet, 4 to 6 inlets, and water inflow in one direction, so that the water forms a circulation, so that the residual bait and excrement can be discharged smoothly. In order to prevent the flounder from jumping out, the pool wall should be 30cm ~ 50cm above the water surface.

The species of Japanese flounder can be caught directly from the natural sea area or purchased from the farm, and the quality of the latter is better. Fish species can be entered when the water temperature of the culture pond is above 13 ℃. It is required that the total length of the fish is more than 10 cm, the body color is the same, the pattern is clear, similar to the natural color, no albino, blackening phenomenon, strong physique. If you put it in the palm of your hand, it is better to feel the fish bounce forcefully. Fin decay, redness and hyperemia on the body surface and diseased gills should not be allowed. The stocking density is 150 ~ 100 tails per square meter with a body length of 10 cm ~ 15 cm and 50 ~ 35 tails per square meter with a body length of 20 cm ~ 25 cm.

The bait of Paralichthys olivaceus should be of good quality, and attention should be paid to the application of the bait at the same time. The main diets used for the culture of Japanese flounder are full-price compound feed and small miscellaneous fish. The main bait fish are jade fish, goby fish, cloud tuna and so on, among which the low fat content jade muscle fish is the best. Generally, bait is given twice a day (7: 00 a. M. and 3: 00 p. M.), and the feeding amount is about 3% of the fish's body weight. When the water temperature exceeds a certain range (> 25 ℃ or < 12 ℃) or takes a medicine bath, it is necessary to reduce the feeding times or stop feeding. Bait should be uniform, avoid long-term feeding of a single bait, so as to avoid undernutrition.

The daily management of Paralichthys olivaceus should be strengthened. Fish species should be sorted properly according to their growth conditions after being reared in the pond for a period of time. The sorted fish not only have high survival rate and fast growth, but also have neat specifications and are convenient for feeding and management. After each separation, 8 × 10-6 10 × 10-6 oxytetracycline or 1 × 10-6 2 × 10-6 furacilin can be bathed for 1 hour ~ 2 hours to prevent bacterial infection caused by abrasions. Pay attention to stop eating before sorting, and operate gently and quickly. When the water quality is poor or there is residual bait accumulation at the bottom of the pool, the method of lowering the water level can be used to increase the water exchange rate, or siphon or cleaning can be used to remove the residual bait. The water exchange volume during the cultivation period is directly proportional to the water temperature and culture density. Generally, when the water temperature is below 15 ℃, the water exchange volume is 5 ~ 10 times per day. With the increase of temperature, the water exchange volume should be increased or the water level should be kept high. In the summer high temperature season, the amount of water exchange should be up to 12 times / day ~ 24 times / day, in order to keep the low water temperature and let the flounder spend the summer safely.

The culture ponds of Paralichthys olivaceus should be sprinkled and disinfected regularly with disinfectants containing bromine and chlorine; to detect them as early as possible, the right medicine, such as gastrointestinal diseases caused by bacteria, can be fed with baits sensitive to pathogens, and parasitic diseases can be washed and soaked with fresh water baths or insecticides. In addition, it is necessary to do a good job of disinfection to prevent the spread of diseases and cross-infection. The sick and dead fish should be buried deeply after being treated with disinfectant, and the culture water where the disease occurs must be disinfected before it can be discharged.