In 2002, Changxing County had 40,000 mu of shrimp aquaculture area, which is the main variety of the county to adjust the structure of the agricultural industry and develop special aquaculture. At present, the comprehensive updating of the original broodstock and improved shrimp germplasm is the basis for raising the economic benefits of the shrimp culture. The use of Taihuqing shrimp breeding shrimp is a good way. The main techniques for the development of shrimp seedlings in Taihu Lake are as follows:
1. Selection of nursery ponds Ponds should be selected for easy access to water, no pollution to water sources, and an area of ​​3 to 5 mu. The depth of water should be 1 to 1.2 meters. No leakage, no sludge and a slope of 1:2 to 3.
2. The cultivation of shrimp seedlings in ponds of clear ponds and sun ponds, clear ponds and wild ponds are one of the key technologies. Fanmian Qingtang is carried out in late April or early May. Each mu uses 100 to 150 kilograms of quicklime or 15 kilograms of bleach to bring clear ponds to destroy wild fish and pathogens in the pond. After one week, the ponds are drained to dry the ponds. The drying ponds should be hardened or cracked after drying in the bottom of the pool.
3. Harvesting and transportation of broodstock During the period from mid-May to early June, the Taihu Lake catching households should be contacted beforehand to request to lay a layer of mesh in the living tanks of the fishing vessels, and to increase the size of the shrimps in order to reduce losses; Impulse pumps and aerators to prevent anaerobic broodstock during transit and increase the survival rate of broodstock.
4. Rearing and management during the period of clearing seedlings After clearing the ponds, inject water 0.6 to 0.8 meters 5 to 7 days before releasing the eggs, and use 60 mesh nets to cover the inlets to prevent wild eggs from invading the pond with water. Apply base fertilizer to make the pond water have a certain degree of fatness. In general, 300-400 kg of organic fertilizer produced in Mushi, or 4-6 kg of compound fertilizer in Mushi, has a transparency of 30-40 cm. Egg-holding shrimp can be grown in a cage or directly into a pond. The cages are stocked at 0.5 kg per square meter, with appropriate amount of water plants, and are fed with bait every day to observe hatching of broodstock. When most of the broodstock are empty, they are splashed with 1 to 2 kg of soybean milk filter residue every day. , In the afternoon and afternoon, each vote; if the water quality is too fat, you should stop feeding. A new amount of water is injected every few days, and the water level reaches 1.0 to 1.2 meters after 12 to 20 days. When changing the water quality, you should consider changing the water so that the water color always stays fat, live, tender and cool. After the juveniles became juveniles, they began to feed the crushed crushing material in an appropriate amount and fed 0.3-0.5 kg per mu per day. When the size of the shrimp reaches 1.5 cm, it can be stocked in ponds.
5, shrimp fishing can be used to release water, pull the net or operate the net fishing three methods. The first method has the advantages of not damaging shrimp seedlings and catching shrimp seedlings with neat specifications and no soft shell seedlings. The specific operation method is: to open the outlet in Tanggu, place the seedling box at the outlet, and control the mesh of the box. Below 14 heads, the pool water is drained so that the shrimp seedlings can enter the seedling collection box along the water. The second method is to use a 25 mesh net to make a pull net, and the net is to pull the net to catch the shrimp seedlings. The third method is to use the hand net to operate the net. Under the water grass, shrimps are caught.
1. Selection of nursery ponds Ponds should be selected for easy access to water, no pollution to water sources, and an area of ​​3 to 5 mu. The depth of water should be 1 to 1.2 meters. No leakage, no sludge and a slope of 1:2 to 3.
2. The cultivation of shrimp seedlings in ponds of clear ponds and sun ponds, clear ponds and wild ponds are one of the key technologies. Fanmian Qingtang is carried out in late April or early May. Each mu uses 100 to 150 kilograms of quicklime or 15 kilograms of bleach to bring clear ponds to destroy wild fish and pathogens in the pond. After one week, the ponds are drained to dry the ponds. The drying ponds should be hardened or cracked after drying in the bottom of the pool.
3. Harvesting and transportation of broodstock During the period from mid-May to early June, the Taihu Lake catching households should be contacted beforehand to request to lay a layer of mesh in the living tanks of the fishing vessels, and to increase the size of the shrimps in order to reduce losses; Impulse pumps and aerators to prevent anaerobic broodstock during transit and increase the survival rate of broodstock.
4. Rearing and management during the period of clearing seedlings After clearing the ponds, inject water 0.6 to 0.8 meters 5 to 7 days before releasing the eggs, and use 60 mesh nets to cover the inlets to prevent wild eggs from invading the pond with water. Apply base fertilizer to make the pond water have a certain degree of fatness. In general, 300-400 kg of organic fertilizer produced in Mushi, or 4-6 kg of compound fertilizer in Mushi, has a transparency of 30-40 cm. Egg-holding shrimp can be grown in a cage or directly into a pond. The cages are stocked at 0.5 kg per square meter, with appropriate amount of water plants, and are fed with bait every day to observe hatching of broodstock. When most of the broodstock are empty, they are splashed with 1 to 2 kg of soybean milk filter residue every day. , In the afternoon and afternoon, each vote; if the water quality is too fat, you should stop feeding. A new amount of water is injected every few days, and the water level reaches 1.0 to 1.2 meters after 12 to 20 days. When changing the water quality, you should consider changing the water so that the water color always stays fat, live, tender and cool. After the juveniles became juveniles, they began to feed the crushed crushing material in an appropriate amount and fed 0.3-0.5 kg per mu per day. When the size of the shrimp reaches 1.5 cm, it can be stocked in ponds.
5, shrimp fishing can be used to release water, pull the net or operate the net fishing three methods. The first method has the advantages of not damaging shrimp seedlings and catching shrimp seedlings with neat specifications and no soft shell seedlings. The specific operation method is: to open the outlet in Tanggu, place the seedling box at the outlet, and control the mesh of the box. Below 14 heads, the pool water is drained so that the shrimp seedlings can enter the seedling collection box along the water. The second method is to use a 25 mesh net to make a pull net, and the net is to pull the net to catch the shrimp seedlings. The third method is to use the hand net to operate the net. Under the water grass, shrimps are caught.