Experience of how to breed crayfish in freshwater over the winter

With more and more lobster farmers in our country. There are more and more techniques for lobster farming. Farmers can communicate and learn from each other and learn from each other's good techniques and methods in order to maximize the profits of lobster farming.

How to breed crayfish in freshwater to survive the winter

In winter, crayfish enter the cave for the winter and grow slowly. Strengthening the overwintering management of crayfish in winter can improve the overwintering survival rate and culture benefit.

The area of the overwintering pond is 3 mu ~ 5 mu, and the slope ratio is 1 ∶ 2.5 mu 1 ∶ 3. Leeward to the sun, sufficient water, no pollution, water depth of more than 1.5 meters. Drain the pond water before releasing the shrimp and thoroughly disinfect it with 75kg of quicklime per mu. 7 ~ 10 days before shrimp release, water was injected and fertilized, and 100kg ~ 150kg of rotten animal manure per mu was applied to cultivate plankton. Transplant aquatic plants such as water hyacinth, water peanut, Malay and other aquatic plants in the aquatic plant pond, with a coverage rate of more than 40% and a uniform layout. Aquatic plants can absorb excess fertilizer in the pool and prevent anoxia through photosynthesis. At the same time, aquatic plants can breed aquatic insects and supplement crayfish animal protein.

Stocking technique of crayfish

1. Stocking should be carried out on sunny or rainy days to avoid sun exposure.

2. Purchase crayfish. If it takes a long time to leave the water, it should be treated slightly before stocking. The shrimp is soaked in the pond water for 1 ~ 2 minutes, lifted and shelved for 2 ~ 3 minutes, then soaked for 1 ~ 2 minutes, repeated for 2 ~ 3 times, and let the shrimp absorb enough water before stocking, which can improve the survival rate.

3. Stocking density. Stocking 150kg ~ 250kg per mu, specification 16 ~ 20 per kilogram, stocking crayfish requires strong physique, uniform specifications, complete appendages, foot release at one time, avoid batch stocking, in order to reduce killing each other.

4. Silver carp and bighead carp can be stocked in the overwintering pond to regulate the water quality and improve the utilization rate of bait.

Daily management of lobster

1. bait at the right time. Feed more animal feed before overwintering to strengthen the physique and improve the survival rate in winter. During the overwintering period, the lobster does not look for food, but when the weather is sunny and warm, the lobster leaves the cave and forages a small amount of food, which can be fed with animal bait such as miscellaneous fish and shrimp, conch clam meat and animal viscera to replenish the body nutrition.

2. Adjust the water quality. During the overwintering period, the water level in the pool should be kept above 1.5 meters to maintain the water temperature of the pool. If the water level is too shallow, it is necessary to replenish the water timely to prevent the lobster from frostbite to death; if the water quality is too fertile, change the water at the right time, keep the dissolved oxygen in the water above 4 kg / L and the transparency above 40 cm, so as to prevent the crayfish from asphyxiation due to hypoxia.

3. Patrol the pool regularly. Patrol the pool twice a day, find abnormal and take countermeasures in time. During the overwintering period, every 10 to 15 days, 20 kg of quicklime per mu was sprinkled in the whole pool to disinfect the water body, replenish calcium and prevent diseases.

Conditions for culturing freshwater lobster 1. The pond should be rectangular, with an area of 1334 to 3335 per square meter and a water depth of about 0.9 to 1.5 meters. 2. The bottom of the pool is hard soil or sandy, there is no silt, and the wall of the pool must have a certain slope. 3. The pond should have a good drainage and irrigation system, with water entering the upper part of the pond, drainage at the bottom of the other end, and an anti-enemy and escape net cover at the inlet and outlet.

4. There should be an appropriate area of submerged plants at the bottom of the pond, and there should be enough artificial shelter, such as waste tires, nets, bamboo rafts, etc., for lobster shelter. 5. Aerators can be set up in conditional ponds. 6. The pond should be disinfected before releasing the shrimp fry. If the shrimp pond is newly built, quicklime can be used to clear the pond. If the old fish pond is cultured, the dry pond must be disinfected. In addition to sprinkling quicklime, the predatory enemy organisms such as Loach, catfish, black fish, snakes and rats should also be thoroughly removed from the pond. Water quality requirements mainly use the surface water of unpolluted rivers, lakes, reservoirs and other large water bodies as the water source, and groundwater can also be used as the water source. The freshwater lobster has strong adaptability, and the pH value of water can survive in the range of 6.10 to 9.33, but the suitable value is 6.5 to 9.0, preferably neutral alkali, in order to facilitate the rapid growth of lobster. Although freshwater lobster is tolerant to hypoxia, if it is in a state of low dissolved oxygen for a long time, it will affect its growth rate and survival rate. The pollution of water quality by heavy metals, pesticides, herbicides, oil and methane should also be avoided. Micro-running water or regular addition of new water should be adopted in culture to promote growth.

Shrimp seedling release and daily management shrimp seedling release should be carried out in the early morning or evening on a sunny day. Before release, a small amount of pond water is slowly added to the seedling transport container to adjust the water temperature. The shrimp seedlings are put into the pond until the water temperature in the container is close to the water temperature. The stocking density is 7.5 ~ 9.0 per square meter, and the specifications of shrimp seedlings in the same pond are neat and consistent. Due to the fast growth of freshwater lobster, exuberant metabolism and large oxygen consumption, the water quality of shrimp ponds should always be kept fresh, generally adding water 15 cm ~ 20 cm per week to make the water quality lively. Make sure there is enough dissolved oxygen. The bait should be put at a fixed point, at a fixed time and in a fixed quantity, and the types should be diversified as far as possible, and should be fed once every morning and evening, and the bait should be placed on the shallow edge of the pond. Crayfish has six major characteristics: first, large and fat; second, fast growth and high yield; third, rich nutrition and delicate meat; fourth, strong adaptability and can survive in bad weather and environment; fifth, miscellaneous food habits, not only can eat animal feed, but also can eat artificial compound feed and humus; sixth, high economic benefits.

In fact, whether it is lobster farming or other aquaculture industries, there are certain risks, and farmers need to be prepared to undertake these before breeding. It is best to fully understand some of the crayfish's living habits before breeding.