The first is the clearance of fry.

Choose shrimp seedlings with neat stocking specifications, strong physique, strong activity, complete appendages and no injuries. Generally, the stocking size is 2 ~ 3 cm, and the density is about 6000 pieces/mu. First, put the shrimp into the pool water 1 ~ 2 minutes, then take it to the edge of the pool and let it stand for 3 ~ 5 minutes. Repeat this for 2 ~ 3 times to make the surface and gill cavity of the shrimp absorb enough water, and then slowly put it into the pool along the edge and fill it up at one time. Shrimp seedlings should be soaked in 3% ~ 5% salt water for 5 ~ 10 minutes before entering the pond to kill pathogenic bacteria and parasites. The stocking time is April.

Second, the feed gap

Crayfish is an omnivore, especially likes to eat animal bait, and is greedy by nature and eats a lot. Therefore, the compound feed with comprehensive nutrition and moderate feeding amount should be selected for feeding. If the feeding amount is insufficient, it will affect growth and even kill each other. If the feeding amount is too large, it will cause feed waste and pollute the water quality. The protein content of young shrimp fed with compound feed is about 35%, and that of adult shrimp is 28% ~ 30%. Feeding twice a day, morning and evening 1 time, before sunrise in the morning and after sunset, mainly at dusk, accounting for 70% of the daily feeding. The daily feeding amount is 2% ~ 3% in the early and late stages of culture, and about 5% in the middle stage. Feeding should adhere to the "five-fixed" standards of qualitative, quantitative, timing, positioning and personnel. The feeding amount with rest should be controlled sensitively according to the weather, water quality, shrimp growth, etc. Generally, it is appropriate to eat and eat without leaving residual bait.

Third, water quality control.

Adhering to good water quality is beneficial to the healthy growth of crayfish. Fill 1 time with fresh water every 7 ~ 10 days, add 20 ~ 30cm of water each time, and change the water 1 ~ 2 times a month, changing the young and old by about 30% each time, and maintaining the visibility of 30 ~ 40 cm. Sprinkle 1 time of quicklime every 10 ~ 15 days, with the dosage of 10 ~ 15 kg/mu, and adjust the pH value to 7.5 ~ 8.5. Spraying photosynthetic bacteria such as gold 1 time per month, combined with biological agents such as gold culture stock solution, can reduce toxic and harmful substances such as ammonia nitrogen, nitrite and hydrogen sulfide in ponds and improve water quality and sediment. Usually, the aerobic equipment should be turned on frequently, and the dissolved oxygen in the pond should be above 5 mg/L, so that the shrimp in the pond can grow happily while enjoying the "oxygen regulation".

Fourth, the management of molting

The metamorphosis, regeneration and growth of crayfish larvae always stop with molting. Only by peeling off the hard shell can we grow and develop. Therefore, it is particularly important to strengthen the management of hulling period. We should mainly start from four aspects: First, adhere to the "fat, lively, tender, cool and stable" water quality. The second is reasonable feeding. The third is to maintain aquatic plants.

Verb (abbreviation of verb) disease prevention and control

The prevention and treatment of crayfish diseases should adhere to the principle of "prevention first, separation of prevention and treatment, prevention before disease, and early treatment of disease". Measures such as strict pond cleaning and disinfection, putting in high-quality fry, creating ecological environment, feeding new feed and feeding medicinal bait regularly can effectively prevent the outbreak of shrimp diseases. Once the shrimp in the pond get sick, it is necessary to diagnose the cause in time and choose the medicine according to the symptoms, so as to achieve early treatment, early control and early effect, and minimize the loss.

6. Enemy invasion.

The main enemies of crayfish are voles, frogs, waterfowl and some fierce carnivorous fish. These animals can prey on crayfish, and measures should be taken to kill them in time. About carnivorous fish, when adding water, it can be filtered with a dense net to prevent them from entering the pond. Rats can be killed by traps and cages; For birds, some colored stripes can be set beside the pool, and the scarecrow can stop threatening and expelling. For frogs, artificial catching can be stopped at night.

Seven, waste quality.

Strictly implement the consumption norms of pollution-free aquatic products, prohibit the use of illegal drugs and inputs, strengthen water quality and feeding management, and ensure that the cultured commercial shrimp is of high quality, good taste, no residue and no pollution.

Eight, timely salvage and removal

After careful rearing of crayfish for about 2 months, the specifications of some shrimps reached more than 30 grams. At this time, you can start fishing in shrimp cages and underground cages, catch the big ones and keep the small ones, reduce the density of shrimp in the pond and promote the rapid growth of small-sized shrimp.