1, broodstock selection can be selected from September to October in the previous year or March-April of the year to choose broodstock, requires weight 30-50g, appendages complete, healthy and disease-free, strong activity, male to female ratio of 2-3:1. Male and female lobsters have obvious features in appearance and are easy to distinguish. 1 Mature lobsters, the male individuals are significantly larger than the females; 2 The males have large foot and there is a bright red soft palate on both sides of the dragon feet. The female dragon feet are relatively small, and most of the female feet do not have red soft palate. The color is also subdued; 3 male gonopore openings in the fifth pair of foot foot base, female genital hole is open in the third pair of foot foot base; 4 sexually mature female abdomen enlargement, the male abdomen is relatively small. 2, broodstock broodstock cultivation pool area of ​​1200m2 or so is appropriate, the bottom soil in loam is good, water depth of about 1m, pond width of more than 1.5m, there is ample and good water, built note, drain outlet, four weeks pool use The plastic film or calcium plastic plate is built to prevent escape of the wall, and the pond is disinfected with 50-60 kg/kg of lime dry pond before 7-10 days of stocking. After the disinfection, the water is filtered by the filter (the wild fish is prevented from entering the pond) and the water depth is about 1m, and the decomposed livestock and poultry manure is used to fertilize water of 500-800kg/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 to feed broodstock 40-60kg/mu, and 3% salt water is used for bathing for 10 minutes before stocking to kill pathogens. In order to make full use of the water body and regulate the water quality, 50-100 tails per mu can be mixed. 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, it is 2%-3% of broiler weight, 4%-5% in April, 6%-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 water quality management, change fresh water once every 10-15 days, change water 1/3 each time; use lime every day for 10-25g/m2 dipping water once to maintain good water quality, promote gonad development . 3, broodstock breeding 4-5 months, water temperature above 20, broodstock began mating. Fertilized eggs hatch into juvenile shrimp in the female's abdomen, and incubation 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, the broodstock winter lobster survival water temperature is the lowest value of 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 many deaths after 2-3 months. Therefore, do a good job of wintering for broodstock and ensure that the water temperature during the winter is between 16°C and 18°C, which is also an important part of the 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. 5. Although the amount of eggs held by lobsters is not large, the fertilization rate can be above 98%, and the hatching rate can reach 80% to 85%. The problem is that post-emergence growth of clams is frequent and susceptible to environmental conditions that affect seedlings. To improve the seedling raising rate, the following points must be made: 1 Water quality requirements During the breeding of lobster, it is necessary to keep the water body relatively stable, the water quality is fresh, the pH is between 6.5-8, and the water temperature difference between day and night is prevented; the dissolved oxygen in the water should be maintained. 5.6 mg/l or more. 2 water environment water surface must have water lotus (accounting for 1/3), the bottom of the best water plants, and hidden caves, increase shrimp seedling clam shell attachments, but also easy to check the seedlings by water lotus seedlings to check the time And the growth of shrimp. The water inlet is equipped with a fence and a filter to prevent the entry of predators into the pond, while preventing frogs from entering the pool and spawning eggs to avoid sturgeon. At the same time, it is necessary to prevent the brooding shrimps from climbing. 3 strengthen the inspection persist in checking the emergence of the situation in the morning and evening, when the larvae free mother, promptly catch the broodstock back to the broodstock pool and then nurture, try to reduce the inventory over the pool, the operation should be particularly careful to avoid the broodstock and newly hatched broodstock The prawns have an effect. 4 Ensure that feeding is carried out. Small zooplankton, such as rotifers, are used to feed fresh hatchlings. It is estimated that 3-5 days before hatching, a small amount of small zooplankton will be caught from the special feed pond to enter the shrimp pond. And use cooked egg yolk, soy milk and other timely feed supplements for young and young shrimp. 6. Cultivation requires juvenile shrimp to leave the mother's life, usually in the young shrimp pond. After all the juvenile shrimp leave the mother, the broodstock is removed and young shrimp are left for cultivation. At this time, the average length of the young shrimp is 0.8 cm. After 15 days of cultivation, the body length can reach 2.4-3 cm for the farmers to produce shrimp. (1) The nursery pond requires that the cement pool with an area of ​​20-40m2 and water depth of 0.6-0.8m is preferred for the young shrimp ponds, and the earthen ponds can also be used. However, the new cement pools must be treated with alkali beforehand, requiring close proximity to the water source and good water quality. , Drainage is convenient, anti-escape facilities are built, and ponds are sterilized (the same method as broodstock breeding). After the disinfection, 500 kg/mu of organic fertilizer was applied, and plankton was cultivated for feeding by juvenile shrimp. At the same time set up tree roots, bamboo tube, etc., to provide young shrimp habitat, shells and hidden places. (2) Water requirements 1 Water quality Generally, river water or well water is used, and the water quality should be fresh. At the inlet, filter the influent water with a screen to prevent insects, aquatic animals (such as otters), small fish, shrimp and eggs from entering the pool. During the cultivation period, depending on the residue feed and water quality (such as ammonia nitrogen and other high levels of tri-state nitrogen), it is necessary to regularly change the water to maintain good water quality. 2 The suitable water temperature range is 27°C to 29°C, and the range of change cannot exceed 2°C. If the water temperature is lower than 20°C, the growth rate will decrease, which will seriously affect the survival rate. Therefore, the water temperature should be kept relatively stable during the entire cultivation period. 3 Dissolved Oxygen The juvenile shrimp leave the mother's body and the cultivation pool must be continuously inflated throughout the day so that the dissolved oxygen in the water is sufficient. The PH value of the 4PH cultivation water should be controlled at 7-8.5, which is alkaline. If the water quality is found to be acidic, quicklime can be used to adjust the PH value. With the tap water for the small-scale production of the breeding ground, baking soda can be used to adjust the PH value. 7. Cultivating Technology Young juvenile stocking amount is generally 150 to 230 tails/m2. Note that the specifications of the shrimps in the same pool are the same, and choose sunny morning or cloudy days. After 1 week of stocking, soybean milk can be fed for 3-4 times a day. From the 2nd week on, animal feeds such as small fish, snail meat, cockroach and silkworm cocoon are mainly fed. Paste feed, 1 shot each in the morning and evening, 40% of the daily bait amount in the morning, and 0.25-0.40kg per 10,000 juvenile shrimps in the early days of feeding, and about 10% of the shrimp weight will be fed later. During the cultivation period, change the water once every 10 days for 1/3 of each time; splash lime water once every 20 days, the concentration is about 20g/m3 to adjust the water quality. After 25-30 days of cultivation, the juveniles can grow up to 3cm in length and can be transferred into shrimp culture.
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