What are the reasons for the failure of crab farming? How to raise it so as not to die?

It is now the season to eat crabs, and the price of crabs has been high all the time, so it can be seen that raising crabs still makes a lot of money. however, the crabs cultivated by many people are either dead, or have no production, or have no specifications, and the key to raising crabs is skill. if you need professional guidance on crab farming, what is the reason for the failure of crab farming? How to raise it so as not to die?

First, what are the reasons for the failure of crab farming?

If you want to raise crabs well, you need to know what causes crab death, lack of specifications, and lack of production. Analyze them from the following aspects:

1, seedling: crab seedling selection is very critical, must choose high-quality crab seedlings, as far as possible to take the original pond seedlings, the shell is not fresh, no vitality can not be asked for, the purchase of crab seedlings is best to go to large-scale farms to actually inspect the situation or.

2. Weather: sometimes bad weather will affect the output, so we should pay more attention to the weather conditions at ordinary times. The continuous rainy weather of crab shelling and second shell, as well as the continuous high temperature in the later period will affect the specification and output. At this time, we should take precautions.

3, drug residue: now many farmers like to use trichlorfon and pyrethroid drugs to clear the pond, although the pond cleaning effect is good, but the drug residue problem is serious, affecting the shelling growth of crabs.

4. Water quality and aquatic plants: crabs have to go through five times of shelling, and attention should be paid to water quality and aquatic plants after shelling from the second shell. At least two or more kinds of aquatic plants should be planted in the pond, not just a single one. In the middle and later stages of culture, we must plant some high-temperature-resistant aquatic plants, such as verticillium verticillata, bitter grass and so on.

5. Others: the rupture of the escape net leads to crab escape, man-made theft and so on, all of which will be affected, but these are not important, just pay more attention to observation.

Second, how can crabs not die?

If you want your crabs not to die, the most important thing is to master the technology and have professional guidance, starting from the following aspects:

1. Pond conditions: convenient transportation, convenient entry and drainage, abundant water source, good water quality, no pollution, flat bottom.

2, crab seedling selection: choose good quality crab seedlings, generally choose neat specifications, disease-free and injury-free, physically strong, crawling active crab fry.

3. Aquatic grass planting in pond: the yield of crabs mainly depends on the number of aquatic plants and bait organisms. Aquatic plants are one of the natural baits that crabs like to eat, and they also have the function of purifying water quality, and they are also places for crabs to perch and avoid enemies. The area should account for more than 70% of the pond area, and the main varieties are verticillium verticillata, bitter grass, Elaeagnus, duckweed, Manjianghong, water hyacinth, water floating lotus and so on.

4. Pond sterilization and disinfection: pond cleaning disinfection must be done well, mainly killing wild mixed crabs, enemy organisms and various pathogens in crab ponds. Every winter, excessive silt in crab ponds should be removed in time, so that the silt at the bottom of the pond should not exceed 10 cm. Medicine cleaning pond should be carried out 10-15 days before releasing crabs. According to the situation of water source, dry cleaning ponds can be sprinkled with quicklime 75kg or bleach 4~5kg per mu. Or clean the pond with water for raw lime 25 mg / kg or bleach (containing more than 25% available chlorine) 1 mg / kg sprinkled throughout the pool.

5. Anti-escape facilities: anti-escape facilities are set up according to the type of culture. Anti-escape facilities for raising crabs in ponds are anti-escape ditches and walls; lake fences are equipped with bamboo foil, walls, bottom cages and so on.

6. Seedling release: pay attention to the temperature difference when releasing seedlings. The purchased seedlings should not be directly put into the pool. Soak in water for 3 minutes, take out and put in for 10 minutes, and repeat 2murf for 3 times, so as to improve the survival rate.

7. Pond water quality control: the water quality of cultured crabs is also critical. The pH value of crab pond water is the most suitable between 7.5 5MG/1 and 8.5. The dissolved oxygen in the pond water is kept above 2MG/1, and crabs will die if it is below 2MG/1. Therefore, quicklime should be used regularly to adjust and improve the water quality. Pay attention to changing fresh water frequently, keep the water level 0.6-0.8 meters, adjust it to 1-1.2 meters in high temperature season, change water every 7-10 days, change water every 3 days, and inject 10-20 cm of water every day.

8. Bait in the pond: crabs are omnivorous animals. Before crab breeding, 300-500 kg of snails per mu are put in order to cultivate the basic bait of crabs; on bait feeding, one time each time in the morning and evening, mainly animal bait at the initial stage of stocking, and then gradually increase the feeding of plant-based concentrate fodder. If you want to meet the specifications of crabs in the later stage of breeding, plant concentrate feed and animal bait should be added. Crab feeding method is mainly based on the season, weather, water quality, crab activity, timing, fixed point, fixed quality, quantitative release.

9. Crab diseases: at present, many kinds of crab diseases will cause a large number of deaths, and the incidence area is large, and the incidence season is irregular. Throughout the whole process of breeding, crab disease prevention is more important than cure. The main diseases are edema disease, rotten limb disease, ciliosis, trembling disease, black Gill disease and so on. Preventive measures should be taken according to different conditions.

10, crab fishing: generally enter October, according to the temperature and market conditions, timely fishing on the market.

Conclusion: this is a brief introduction to crab farming. I hope it will be helpful to everyone. Crab farming must be intensive, and it is best to go to a place where you are specialized in breeding to learn relevant technical knowledge and scientific management. only in this way can you ensure that the crabs you raise will not die and lead to low output.