I. Breeding facilities
The suitable pond area is 4 ~10 mu, the depth is1~1.5 m, and the slope ratio is1:2.5. The bottom of the pond is flat, loam is the best substrate, the soil of the pond slope is hard, the water retention of the pond is good, and the water level is easy to control. The water is abundant and the water quality is pollution-free. According to the pattern of high irrigation and low drainage, the drainage channel is built to ensure that irrigation can be carried in and discharged. The crayfish has strong escape ability, so it is necessary to build anti-escape facilities. Usually, plastic film or calcium-plastic board is used, and bamboo piles or wooden stakes are used to support and surround the pond ridge to prevent escape.
Second, preparation before stocking
1, Thoroughly clean and disinfect the pond 20 ~ 30 days before releasing the shrimp seedlings and shrimps, drain the pond water, remove excessive silt, repair the pond ridge, and thoroughly clean and disinfect the pond with 75 kilograms of quicklime or bleaching powder, bleaching powder essence and other drugs per mu.
2. Apply sufficient base fertilizer and 500-600 kilograms of decomposed livestock manure per mu to cultivate rotifers, cladocera and copepods plankton and provide palatable bait for shrimp seedlings and species.
3. Plant aquatic plants such as Hydrilla verticillata, POTAMOGETON malayi and Elodea malayi in the aquatic plant pond, accounting for 2/3 of the shrimp pond area. At the same time, set up nets, or set up bamboo tubes, plastic tubes, etc., to provide perching, molting and hiding places for crayfish.
Third, stocking shrimp seedlings and shrimp species
1, a variety of breeding modes can be adopted. (1) Summer stocking mode. The first batch of young shrimps hatched in the same year are mainly stocked, and the stocking time is in the middle and late July, and the size of young shrimps is more than 0.8 cm. Stocking 30,000 ~ 40,000 tails per mu. (2) Autumn stocking mode. The large-scale shrimp fry or shrimp species cultivated in the same year are mainly stocked, and the stocking time is from mid-August to September. Shrimp fry size 1.2 cm, 25,000 ~ 30,000 per mu; Shrimp species with a size of 2.5 ~ 3cm should be stocked1.50,000 ~ 20,000 per mu. A few of them can reach the market specifications by the end of the year, and most of them will be caught and listed from June to July of the following year. The commercial shrimp weighs only 25 grams and the yield per mu is 300-500 kilograms. (3) Winter and spring stocking mode. Generally, it is stocked in1February or March-April of the following year. Shrimp that did not meet the market specifications in that year were mainly stocked, with the specifications of 0/00 ~ 200 per kilogram10.5 ~ 20,000 per mu. After breeding in winter and spring, it will be caught in the market from June to July. The weight of commercial shrimp can reach 30 grams and the yield per mu is 400-500 kilograms.
2, fry quality shrimp fry quality requirements are: (1) specifications are neat. The size of juvenile shrimp is above 0.8 cm, and the size of shrimp species is about 3 cm. The specifications of shrimp seedlings and species stocked in the same pond should be the same, and they should be fully stocked at one time. (2) Strong physique, complete appendages, no disease or injury, and strong vitality. (3) Shrimp seedlings and species are cultivated artificially. If it is a wild shrimp species, it should be domesticated for a period of time before stocking, so as to avoid fighting and killing each other.
3. Precautions: (1) Winter stocking should be carried out in sunny morning, and summer and autumn stocking should be carried out in sunny morning or rainy day to avoid sun exposure. (2) Wash the shrimps in 3% ~ 5% salt water bath 10 minute before stocking to kill parasites and pathogenic bacteria. (3) Shrimp species purchased from other places should be treated slightly before stocking because they are out of water for a long time. Soak the shrimp seeds in the pool water for 1 min, lift them for 2-3 minutes, then soak them for 1 min, and repeat this for 2-3 times, so that the surface and gill cavity of the shrimp seeds can absorb enough water before stocking them, so as to improve the survival rate. (4) In the pond where crayfish are raised, some silver carp and bighead carp are mixed appropriately to improve water quality and make full use of bait resources.
Fourth, scientific feeding
The crayfish are omnivorous and gluttonous. Feed feeding, grasp the following three points.
1, according to the nutritional needs of crayfish in the same growth stage, do a good job in feed combination and feeding. In the juvenile and juvenile stages, crayfish feed on rotifers, cladocera, copepods and aquatic insects larvae, while in the adult stage, they eat both animal feed and plant feed. After stocking shrimp seedlings and shrimp seeds, fertilizer should be applied at the right time to improve the water quality. In the rapid growth stage of crayfish from August to10, more bran, bean cake and green feed were fed, and animal feed was properly fed. 11~1February, crayfish were mainly fed animal feed before overwintering.
2. Feed crayfish according to their living habits and feeding characteristics. Crayfish crawfish mostly move for food at night, and have the habit of fighting for food and gluttony. Feed should be fed once every morning and afternoon, mainly once in the afternoon, accounting for 70% of the whole day's feeding; Adopt the method of feeding at fixed quality, fixed quantity and fixed time, feed enough and evenly, ensure that each shrimp is full and avoid competing for food.
3. Feed the shrimp reasonably according to the weather, water quality changes and the feeding situation of shrimp activities. The suitable water temperature for the growth of crayfish is 20 ~ 32℃. In August ~1October, the feeding amount of crayfish is large, and the daily feeding amount can be arranged according to 6% ~10% of the shrimp weight in the pond, and the dry feed or compound feed should be 2% ~ 4% as a whole, and it should be appropriately increased or decreased according to the weather, water quality and shrimp foraging. Continuous rainy weather or water quality is too strong, you can feed less, and feed more when the weather is fine; Feed a large number of shrimps less when molting, and feed more after molting; Shrimp should be fed less in the onset season and more when it grows normally. It is necessary to make shrimp eat well, reduce waste and improve feed utilization.
V. Daily management
1, establish a patrol pool inspection system. Patrol the pool every day, and take countermeasures in time if any abnormality is found.
2. Control water quality. Keep the dissolved oxygen in the shrimp pond above 5g/L, the pH value is 7 ~ 8.5, and the transparency is about 40cm. Change the water every15 ~ 20 days, and change the water every time13. Sprinkle quicklime water every 20 days, and use quicklime 10 kg per mu at a time. Keep the water level stable, not up and down.
3, strengthen the management of habitat molting sites. There are always many aquatic plants in the shrimp pond. It is forbidden to disturb a large number of shrimps when molting, and feed high-quality palatable feed immediately after molting to prevent killing each other and promote growth.
4. Prevent escape and disease. Strengthen inspection in flood season to prevent shrimps from escaping. Do a good job in disease prevention and enemy damage removal.
Six, commercial shrimp fishing and transportation
1, fishing. It can be fished intensively from June to July and11~1February. First use tools such as cage net and hand-copied net to capture, and then capture in dry pool. You can also catch big and keep small, and fish all the year round.
2. Transportation. Commercial shrimps are usually shipped dry in styrofoam boxes, plastic bags or refrigerated trucks. Keep the shrimp moist during transportation, and don't squeeze it to improve the survival rate of transportation.