At present, most crab farmers still adopt the rapid crab cultivation method that was cultivated in the year when the early-stage seedlings were cultivated in the same year. This has resulted in small size, poor quality, low price, and weak market competitiveness. In view of this, the author advocates the idea of ​​“climbing crabs and raising crabs”. During the operation, we concluded that the key to nurturing crabs is to control their growth speed.

First, pond conditions.

The area of ​​the pond is 667~1334 square meters (1~2 mu), suitable for water supply, water drainage (consisting of two sets of channel facilities), water quality is fresh and pollution-free, the ponds and weeds should remain abundant, and they should be fished in time if there is a shortage. Transplantation of water peanuts, Vallisneria, etc., water plants control the total area of ​​the pond about 40% to 60%.

Second, anti-escape facilities.

As juvenile crabs have strong turbulence and phototaxis, the water inlets and outlets are tightly sealed with tight meshes to prevent crabs from running, and 60 cm of calcium-plastic plates are used around the pond to prevent escape. The inside inclination is 5 degrees.

Third, the selection and transportation of crab seedlings purchase time.

In the middle of May, it is difficult to achieve the desired results too early or too late. The selection of high-quality crab seedlings can be performed using the "see two questions and three investigations" method. A look at the appearance of crab seedlings: complete limbs, uniform size, active and powerful; the second question finger asks the origin of the pro-crab, and the second asks the desalination time. Generally, after 5 to 6 days of desalination, the Yangtze River water-based crabs can be cultured; The investigation refers to the investigation of the original records of the nursery, the status of the parent crabs in the second pool and the parents in the pool, and the investigation of the medication in the field. When crab seedlings are transported, the bottom of the crab seedlings is placed on the bottom of the box, and the crabs are placed on the top of the crabs for dry transport. Each box can hold 0.5 to 0.75 kg of seedlings. After 24 hours, no damage is caused.

Fourth, the cultivation of young crabs

In order to improve the utilization rate of crab seedlings, the crabs are first cultivated in the middle, and then the crabs are cultivated in separate ponds. That is, 2 to 40 thousand juvenile crabs per 667 square meters. After the middle cultivation, the survival rate of the crabs was improved by 10% compared with direct investment.

V. Premature control and strengthening management

Preventing precocious puberty is the key to nurturing deduction crabs. Therefore, in the whole process of nurturing crabs should be done:

1. Control density. Overstocking is too dense and the size of buttoned crabs is too small. When stocking is too thin, the proportion of precocious puberty is high. The appropriate density is 20,000 to 20,000 to 2 to 40,000 juveniles that are raised in the middle, ie, 1 to 2 kg.

2. Water quality supervision. Generally, change the water once every half month, splash lime 1 time, strengthen the water quality management in high temperature season, change the water when the shell is forbidden.

3. Reduce accumulated temperature. In the summer season, increasing water depth can control the accumulation of effective accumulated temperature of young crabs.

4. Reasonable feeding. When the crabs first entered the pool, they were fed a small amount of animal feed, which accounted for 20% of the body weight of the crabs. Afterwards, the amount of bait was reduced step by step and was generally controlled at about 8% to 10%. At the same time, the ratio of animal feed was reduced, and plant food was increased. .

5. Winter management. Before winter, the pond water level is increased to 1.2~1.5 meters, and at the same time, 100 kg of fertilizer per 667 square meters of manure is used to check the water quality regularly.

6. Disease prevention and control. It is mainly prevention, focusing on the prevention of hydromycosis, ciliate disease, rotten limb disease, etc. We must also prevent ferocious fish and rat snakes from predators.

7. Get caught for sale. Before and after the Spring Festival, the time of arrest was used to stimulate the water, catch cages, and catch dry ponds.

As long as the cultivation techniques are in place and properly handled, generally about 10,000 crabs can be cultivated per 667 square meters, and the high-yielding ones can reach 1.3 to 15,000, with relatively obvious economic benefits.

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