What are the management details before and after the release of prawns? What are the release times and precautions for crayfish?

The depth of the lobster pond is generally 1.5m long, and the total width of the ridges around the pond is at least 3-4m at the bottom and 1.5m at the top. Set up the entrance and exit of the pool, and take measures to prevent the exit from running. Generally, it is necessary to ensure that there is 15-20 cm sludge in the pool, and the pool mouth moves to the rectangular pool mouth where the best things move, with a separate entrance and exit. Around the pond, a colored tile or color steel roof is erected vertically and fixed in the field. The relative height of the exposed road surface should be at least 50 cm to prevent lobsters from escaping. Every year in June 5438+ 10, the whole pond must be disinfected after lobster removal. You can put water into the depth of 1 m, then grind the water into powder with 50 kg of 1 mu quicklime, and then sprinkle it all over the pond for disinfection and sterilization. After 5-7 days, the water is drained and dried in the pond. Increase the base fertilizer after autumn, which can be used as base fertilizer 1 mu, and the capital investment is less than 200 kg. The base fertilizer invested by the capital should be spread evenly, not in piles.

Pay close attention to the water quality after shrimp larvae are freely stocked. It is often necessary to accurately measure the ph value of water body and observe the clarity and color transition of water body. In general, it is best to keep the clarity of water at 30-40 cm. The water body is light green, and the ph value should be neutral or weakly alkaline, and should not be higher than 9. Use 10KG 1 mu of quicklime with water level per meter to crush water every month, and spray 1-2 times in the whole pond. It is also necessary to change the water in the fish tank once every month 10 hour, and the amount of water changed in the fish tank is about 25% of the water in the whole pond, and the bottom-changing particles are thrown once every 15 days to improve the natural environment at the bottom of the pond.

Living environment of crayfish. Intensive culture of crayfish should meet certain standards. Conditions are not available, and it is difficult to intensively cultivate. According to the regulations of shrimp pond, the general water level is 1 ~ 1.5m, surrounded by ponds and ridges, with a bottom height of 3 ~ 5m and a ridge width of 1m, which is 50㎝ higher than the river surface. The ridge should be equipped with escape net, water inlet pipe and water outlet. The pH value of water should be kept at 7 ~ 8.5, the concentration of water-soluble oxygen should be 3.5 ~ 4 mg/L, the visibility should be 30 ~ 45 ㎝, and the nitrate and dissolved ammonium in water should be below 0.05 and 0.45 mg/L.. The water temperature 15 ~ 30℃ is suitable for growth and development. When it is lower than 10℃, it will enter the cave dormancy state, and the living environment temperature is 1 ~ 40℃. Shrimp ponds should be disinfected on time to prevent diseases. 40% ~ 50% aquatic plants should be planted as food in shrimp ponds.

There are many intensive ponds for crayfish culture in Huai 'an, Suqian and Yancheng of Jiangsu Province. First, you need to find an area suitable for crayfish culture. The standard is: close to the river, the land can't seep, the drainage pipeline is good, and there can't be urban waterlogging in the rainstorm season. Therefore, it is extremely important to choose a breeding factory! Once the site is selected, it's time to start construction. Excavate an annular trench in the foundation pit in the planting land resources contracted by oneself. The annular groove spacing is 3m, the groove bottom width is 1 m, and the depth is 80-120cm. Mud dug out of the annular pit is then laid along the outfield of the annular trench. The function of the dam is to store water and assemble the escape net. Crawfish hibernate to make holes.