Crayfish individuals full, unique taste, rich nutrition, favored by consumers, the current market price is high, artificial breeding prospects have been optimistic. The crayfish pond culture technology is introduced as follows for farmers' reference.

I. Pond conditions

Choose a place near the water source, sufficient water, fresh water, no pollution source, quiet environment, power matching, and convenient transportation. The pond is rectangular, with east-west direction, light shining, good water retention, flat bottom, and silt thickness less than 10 cm. For ease of management, the pond area is generally about 10 acres, with a pool depth of 1.2 to 1.5 meters and a pool slope ratio of 1:3. In the middle of the pond, several mud louses are set. The length of the loach is about 4/5 of the length of the pond, and two ends are not connected to the pond to facilitate the navigation of the aquaculture production boat; the raft is more than 1 meter wide and the cormorants rise 5 to 10 centimeters above the water surface. Create burrowing places for crayfish. The pond should also have an independent intake and drainage system so that it can discharge energy. Each pond should be equipped with micropore oxygen aeration facilities with a power of 0.2 kilowatts/mu and an aeration pipe length of 30 to 40 meters/mu in order to increase aquaculture production and improve product quality.

Second, prepare before restocking

1. Clear pond disinfection. The pond was drained in winter and the ponds were trimmed to remove excessive silt. The silt was kept about 10 cm thick. The height of the pond was increased and widened and the pool ponds were tamped. The pool slope was repaired and the bottom of the pond was leveled and exposed to light for about 20 days. 15 to 20 days before planting, 5 to 10 centimeters deep water injection, with lime to 100 ~ 150 kg/mu amount of the whole pool spilled, so that no dead ends. Lime clear ponds can not only kill the enemy's harmful organisms and pathogens, but also play a role in improving water quality and increasing calcium, which is conducive to the growth of crayfish clams.

2. Seine escape prevention. Crayfish have a strong ability to escape, so the pool around the use of plastic nets to prevent escape from the wall, buried under the net 10 to 20 cm, the upper part of the water 50 to 60 cm. In the outside of the net every 1.5 to 2 meters with wooden stakes or bamboo rafts support fixed, the Ministry of the Internet on the inside of the seam width of 30 cm of calcium plastic panels. Drain openings are surrounded by steel mesh or iron fences to prevent crayfish from escaping.

3. Planting snails. The plants cultivated in the crayfish culture pond mainly include Hydrilla verticillata, Elodea, Vallisneria, Goldfish, Eichhornia crassipes, water peanuts, and water duckweed. In accordance with the requirements of even distribution, plants were planted in the shape of “wells” in the center of the pool. Plants were planted in the “mouth” shape at a distance of 1 meter from the edge of the pool. Water plants can not be planted too densely to meet the normal swimming and living needs of crayfish. The collocation of aquatic plants should be reasonable. Elodea and Vallisneria should be planted around the pond, and black algae and water peanuts should be planted in the middle of the pond. In order to increase the overall economic benefits, vegetables, fruits and vegetables can be grown on the slopes of the pond, and rice, white rice, arrowheads and other crops can be planted on the loach in the middle of the pool for human consumption. After planting aquatic plants, put snails before and after Ching Ming and put them in amounts of 300-400 kg/mu to allow them to reproduce naturally, providing a steady stream of animal feed for crayfish; ~200 kg/mu. The timely delivery of snails in the shrimp ponds will help regulate water quality, reduce costs, improve quality, and increase production.

4. Shrimp pond fertilization. The purpose of fertilization is to increase nutrients in the pond water, enable plankton and aquatic plants to rapidly grow and reproduce, inhibit the occurrence of moss, promote photosynthesis, and provide sufficient natural food and dissolved oxygen for crayfish. After the snails are thrown, the fermented livestock manure and other organic fertilizers are applied to the shrimp ponds, and the amount of the applied fertilizer is 300-500 kg/mu. After 20 to 30 days, nitrogen and phosphate fertilizers can be topdressed. The principle of “timely, small amount, and diligent application” should be mastered. The amount of fertilizer to be applied depends on the condition of water and fat, so as to maintain the water quality of the pool.

Third, shrimp species stocking

The crayfish that are stocked are required to have the same specifications, individual fullness, strong physique, strong vitality, smooth surface, no attachments, complete attachment without damage, and the same pond stocking specifications should be the same, one-time release. There are mainly two kinds of stocking methods: First, ponds for newly-built or first-cultivated crayfish are directly stocked with broodstock after disinfection in clear ponds, allowing them to naturally breed shrimps and then grow into commercial shrimps for sale. The sex ratio of broodstock is 1.5-2:1, the specification is 20-40 tails/kg, and the stocking density is 8-12 kg/mu. Second, ponds that have been cultured with crayfish have been caught from August to September. They have been sterilized at the end of September and early October, and have been used to kill traps with drugs that kill the crustaceans. shrimp. Choose local breeding and stocking of juveniles purchased in the Lake District. Stocking specifications are 4 to 5 centimeters, and the stocking density is 10,000 to 15,000 tails/mu. The stocking time is in mid-late or late spring of October. In addition, in order to make full use of the aquaculture water space, it is possible to use oysters, clams, and carp fingerlings that have no clash with crayfish on the ecology and diet. The stocking size of carp fingerlings is 50 to 100 g/tail, the stocking density is 50 to 100 tails/mu, and the stocking time is at the beginning of May; the density of summer flowers for carp and catfish is 3,000 to 5,000 tails/mu, stocking The time is in early July; the stock size of carp fingerlings is 5-6 cm, stocking density is 20 pigs per mu, and stocking time is in late May. The above-mentioned seedlings were soaked for 3 to 10 minutes with 3% to 5% salt solution before stocking to kill harmful bacteria and parasites.

Fourth, management technology

Feed feed. A large number of rotifers, cladocera, copepods, and aquatic insect larvae can be cultivated in the aquaculture ponds by applying basal fertilizers and fertilizers at appropriate timings to feed juvenile shrimp and newly hatched shrimp. In the larvae and adult shrimps, they are mainly fed with compound feed and supplemented with a small amount of fresh animal feed. The feed protein content of juvenile shrimp should be greater than 30%, and the feed protein content of adult shrimp should be above 26%, supplemented with some animal feed. Feed 2 times a day, feed 1 time in the morning and evening, feed it before sunrise in the morning, feed 20% to 30% of the daily feed, and feed it in the evening after the sun goes down. The amount of 70% to 80%, and adjust the feeding amount according to the specific situation.

2. Water quality management. 1 Adjust the water level. Pond culture of crayfish is usually maintained at a depth of about 1 meter, and can be slightly increased during hot seasons and wintering. Throughout the farming process, the water level must remain relatively constant and do not fluctuate so as not to affect the growth of crayfish. 2 regulate the water quality. Change the water every 15 to 20 days 1 time, change the water 30% each time, keep the transparency of the pool water at 40 centimeters; spill lime once every 20 days, the dosage is 10-15 kg/mu, and the pH of the water is controlled at 7.0- Between 8.5; often use microporous aeration facility oxygenation, when the microporous aerobic facilities can not be used due to failure, throwing oxygen and other chemical oxygenation agents to maintain the pool of dissolved oxygen above 5 mg / liter.

3. Control of shrimp disease. Prevention and control of shrimp disease should adhere to the principle of "prevention without disease, early treatment with disease, prevention with prevention, and prevention with prevention." The main disease prevention methods of crayfish are as follows: 1 Saprolegniasis. For every cubic meter of water, 400 grams of salt and 400 grams of baking soda are poured on the water. 2 rot disease. Each cubic meter of water is sprayed with 2 grams of bleaching powder on the water. 3 smut. Every cubic meter of water is splashed with 10 grams of methylene blue. 4 tail disease. 15 to 20 grams of tea seed meal soaking solution per cubic meter of water is splashed in the whole pool. 5 ciliate disease. Every cubic meter of water is sputtered with 1.2 grams of complex copper. 6 enteritis disease. Every cubic meter of water is splashed with 0.3 g of dibromohydantoin. 7 algae poisoning. Every cubic meter of water is spattered with 0.3 g of moss on the net and spilled once every three days. When the medication is easy to lack of oxygen, oxygenation facilities must be turned on to prevent crayfish from floating.

V. Fishing

After 2 months of careful rearing, some crayfish can reach the specifications of the commodity, and the crayfish can reach the market in time for sale in time. This will reduce the density of the crayfish and promote the rapid growth of the crayfish, which also reduces the cost. , an increase in specifications, increase production, improve efficiency, an important measure.

There are many fishing methods for crayfish, which can be trapped by cage nets, cages and other tools. The trapping effect of ground cages is better. Fishing tools are generally placed in aquaculture ponds, placed every afternoon in the afternoon, and cages are caught and caught in the early morning. At the end of the breeding period, the water is drained and all the crayfish and other fish are caught.

COVID-19 Antigen Test Cassette (Nasal Swab)

This detection kit applies immunoassay to directly detect the presence of virus and is possible to reach large-scale testing of up to millions of tests one day

COVID-19 Antigen Test Cassette (Nasal Swab)

NINGBO AUTRENDS INTERNATIONAL TRADE CO., LTD , https://www.metests.com