Brittle culture technique of grass carp

The brittle culture of grass carp is mainly to change the food structure of grass carp to make its meat crisp. The crisp grass carp is called "crispy meat carp" (grass carp is called carp in Guangdong and Guangxi). Its meat is hard and crisp, and it is not easy to be boiled. Even after cutting into fillets and shreds, it is not easy to break, but the meat taste will be more delicious and unique, so as to meet the special taste requirements of consumers and improve the market competitiveness and culture efficiency of grass carp. The brittle culture techniques of grass carp are mainly as follows: 1. Culture conditions. Brittle grass carp culture can be carried out in ponds or cages. Pond requirements: less silt at the bottom, sufficient water source, good water quality, no pollution, convenient access and drainage, an area of 1330 to 2000 square meters, water depth of about 2 meters, thorough cleaning of the pond according to conventional requirements before stocking. Cages can be set in the leeward and sunny places of lakes, reservoirs and rivers. Water body requirements: no pollution, rich in dissolved oxygen, water depth of 47.7 meters, flat sediment and no aquatic plants. A fully enclosed cage with a specification of 5 meters × 4 meters × 2.5 meters and a mesh size of 0.05 meters is adopted. A piece of 30-mesh silk cloth is padded at the bottom of the cage as a feeding platform to prevent feed loss. The new cage should be launched 7-10 days in advance to soften the pieces to prevent scratching the fish; the used cage should be cleaned and soaked in 5% quicklime solution for 30 minutes. 2. Stocking of fish species. Grass carp (Ctenopharyngodon idellus) with strong physique, no injury and no disease, with an average tail weight of 0.5 kg, was selected as fish species. The stocking capacity was 150 kg / mu in pond and 15 kg / m2 in cage. In order to regulate the water quality, the pond per mu can be matched with 50 fish species of silver carp and bighead carp with a stocking body length of 0.13 to 0.15 meters, and a cage with a stocking length of 0.13 to 0.15 meters can be matched with 1 fish per square meter of silver carp and bighead carp. Before stocking, grass carp had better be immunized. If unconditionally, the fish can be soaked in 4% saline solution for 5 minutes for 10 minutes. 3. Embrittlement season. Brittle culture of grass carp can be carried out from the beginning of feeding when the water temperature is above 15 ℃ in spring to the end of feeding in winter. If the culture mode of rotation or batch culture is adopted, the time of each round (batch) of brittle culture should not be less than 60-70 days. 4. Aquaculture management. Feed mainly with high-protein broad beans, plus a small amount of grass, but can not add any other feed. At the beginning, stop eating for 2 to 3 days, then feed a small amount of soaked broad beans (which can be soaked in 1% salt water for 12 hours for 24 hours), and wait until grass carp can be fed regularly and quantitatively. In general, every day around 8: 00 a. M. and 5: 00 p. M. each time, the specific amount of feeding should be adjusted according to the intake of grass carp and the change of water temperature. The daily feeding amount of grass carp at 16 ℃ ~ 19 ℃, 19 ℃ ~ 22 ℃, 22 ℃ ~ 25 ℃, 22 ℃ ~ 25 ℃ and 25 ℃ ~ 28 ℃ was 1.5%, 2%, 3%, 4% and 5%, respectively. When the water temperature is 28 ℃ ~ 30 ℃, the daily feeding amount is 5% ~ 6% of the body weight of grass carp. The daily management work is the same as the routine culture of grass carp.