Key points of management technology of crayfish and river crab polyculture
Key Points of Management Technology of Crayfish and River Crab Polyculture
1. Pond conditions
The pond formation is generally rectangular or irregular polygonal soil pond. The area is 3-4 acres, the pond water depth is 0.8-2 meters, the pond slope ratio is 1: 1.5-2.5, and there are shallow and deep water areas or deeper in the pond. "Well" shape or "back" shape ditch, and equipped with pond microporous aeration facilities. Inlet and drain pipes are set up on both sides of the pond, and the area covered by water and grass at the bottom of the pond is about 60%.
2. Anti-escape facilities
Set up anti-escape fences around the pond, generally made of mesh, plastic film, glass steel tile and calcium plastic board. Generally, the height of the fence is 60 centimeters, of which 20 centimeters are buried in the mud and fixed with bamboo piles, and the pile spacing is 1.2-1.5 meters.
Crayfish seedlings were cultivated by broodstock in the last year. The average broodstock was 10-15 kg per acre; the crab seedlings were released around February, and a total of 480,000 crab species of 120 per kg A total of 480 fish per mu, and 30 fish / silver carp with 10 fish / kg per mu, and 1-2 fish / mu fish with 5-7 cm body length in mid-May.
In addition to putting 300,000 kg of live snails before Qingming to ensure the normal supply of live feed for crayfish and crabs, pellet feed is used throughout the entire production process. According to the different growth periods of river crabs and crayfish, feed them at the right time. Start feeding formula 1 and formula 2 in mid-April. After about one month, feed crushed feed with a particle diameter of 16 mm. Once the crayfish and river crabs are grown, they can be fed with normal crab formula feed. Feed 2 times. From June to July, 100-150 kg of snails should be supplemented per mu according to the situation of snails.
5. Water quality management
Change the water regularly, keep the transparency of the pond water at about 30 cm in the early stage of cultivation, and about 40 cm at the middle and late stages, and use water quality improvers to improve and purify the water regularly. Turn on the aerator at an appropriate time. When the weather is sweltering, you can sprinkle the microbial preparations to improve the water quality. If the water plants at the bottom of the pond are found to be insufficient, 0.5-1 kg of agricultural compound fertilizer can be applied per mu to promote the growth of water plants.
At the end of February, crayfish broodstock were harvested using ground cages. From June to 30-35 g / tail crayfish were caught. River crabs were harvested and marketed around mid-September.