Denilco Environmental technology(Suzhou)Co., Ltd. , https://www.wflood.com
1. Selection of broodstock: broodstock can be selected from September to October of last year or from March to April of the same year, requiring a weight of 30--50 grams, complete appendages, health and disease-free, strong activity, male to female ratio of 2 to 3? 1 . Specific requirements: (1) Mature lobsters, males are significantly larger than females; (2) Males have large feet, and there is a bright red soft palate on both sides of the dragon's foot. The female dragon's feet are relatively small, and most of the female feet are There is no red soft palate, even if the color is light; (3) The male gonopore is open at the base of the fifth pair of step, and the female gonopore is open at the base of the third pair of step-foot; (4) The sexually mature female abdomen Inflated, the male stomach is relatively narrow.
2. Nurturing broodstock
The broodstock pool area is suitable for about 1200 square meters, the bottom quality is loam, the water depth is about 1 meter, the pool width is 1.5 meters or more, there is ample and good water source, and the injection and drainage outlets are built. The plastic film is used around the pool. Or calcium plastic board to build to prevent escape, before stocking 7 to 10 days ponds with 50 ~ 60 kg / kg of lime dry pond disinfection. After disinfection, it was filtered (to prevent wild fish from entering the pond). The water depth was about 1 meter, and the decomposed livestock and poultry manure was used for water quality of 500-800 kg/mu. In the pool, people are provided with concealed objects such as branches, roots, bamboo tubes, etc., and some plants are transplanted.
The broodstock pool can be used for broodstock feeding of 40-60 kg/mu. Before stocking, it is bathed with 3% saline for 10 minutes to kill pathogens. In order to make full use of water bodies and regulate water quality, 50 to 100 tails/mu of cod and eel can be mixed together. During the cultivation period, fresh water grass, bean cake, wheat bran or compound feed can be fed and a part of animal feed can be added. Such as chopped snail meat, livestock slaughtered leftovers and so on. Daily feeding amount: In March, 2% to 3% of broiler weight, 4% to 5% in April, 6% to 8% after May, and 1 feeding each morning and evening, mainly in the evening. It accounts for 70% of the amount of bait. At the same time strengthen the management of water quality, change the new water once every 10 to 15 days, change the water for 1/3 each time; use lime every day for 10~25g/m2 to pour water once to maintain good water quality and promote broodstock Gonadal development.
3. Broodstock breeding
From April to May, when the water temperature is above 20°C, broodstock begin to mate. Fertilized eggs hatch into juvenile shrimp in the female's abdomen, and hatching takes 40 to 70 days. After juvenile hatching, the growth and development of juveniles are completed under maternal protection. When young shrimp leave the mother, they can take food and live independently. When a large number of juvenile shrimps are found in the breeding ponds, the seedlings should be harvested in time for the cultivation of shrimps.
4. Winter broodstock
The lowest survival temperature of lobster is 5°C. However, when the water temperature is lower than 9°C, the mortality rate is high during the overwintering period for shrimps of about 3 cm in size, and although adult shrimps can survive, there are also a large number of deaths after 2 to 3 months. Therefore, do a good job of broodstock overwintering work to ensure that the water temperature during the winter during the 16 ~ 18 °C, but also an important part of the entire breeding work.
The method of overwintering of broodstock is the same as that of Macrobrachium rosenbergii. Commonly used wintering methods include plastic film-covered pool insulation method, electric heater heating method, hot spring water overwinter method, factory residual hot water overwinter method and glass room overwinter method, etc. The safe wintering effect of broodstock.
At present, China's freshwater lobsters mainly come from natural fishing, and the proportion of artificial breeding is very small. Therefore, we should seize this great opportunity in a timely manner and use freshwater lobster culture as the focal point for the development of export-oriented fisheries. We should make full use of natural resources such as ponds, reservoirs, river courses, paddy fields, and beach shoals as well as advanced breeding techniques to maintain a high starting point scale. We will actively develop freshwater lobster culture in accordance with international standards and continue to expand exports. The techniques of selecting and breeding freshwater dragon broodstock are described below.