CATDOLL : CATDOLL: How long can domestic crabs live?

1. How long can domestic crabs live?

1. Tie up the crabs and put them in the refrigerator, preferably on the shelf with the fruits. Spread a wet towel on top of the crabs, don't wring it too dry, and don't fold the towels. This way they can be preserved for a while.

2. Raise the crabs in water. If the crabs are too thin or you want to keep them for a while, you can feed them some sesame seeds or beaten eggs and add some rice wine to fatten them up.

3. Keep it moist. It is no problem to survive for a week or two. Just don't soak it in water. The breeding place is usually placed in a cement pool, sprayed with water every day, sometimes for a month or two.

2. What do crabs eat? How to farm crabs?

Crabs are omnivorous aquatic animals. Their food sources range widely and can be roughly divided into three categories: natural bait, artificial animal bait and artificial plant bait.

1. Stocking. Generally, about 2,500 crabs weighing about 10 grams are stocked per mu. The specifications of the same batch of crabs should be as consistent as possible to avoid individual differences in growth in the future, resulting in a phenomenon of large-scale but small-scale crabs.

2. Feeding. Common aquatic plants, vegetable leaves, various cakes and dregs, small fish, shrimps, earthworms, animal offal, etc. can be used as bait. Generally, the amount of plant bait fed does not need to be controlled, but the animal feed should be adjusted appropriately according to the water temperature.

3. Inspect the pond. In addition to inspecting the pond for fish, you must also pay attention to the activities of crabs. If the crabs crawling on the shore after being frightened in the early morning still do not go into the water, it means they are sick.

If the crabs immediately climb onto the shore after being startled or if a large number of crabs gather on the shore in the evening, it means that there is a lack of oxygen in the pond and water should be added immediately. If crabs are seen cannibalizing each other, more palatable bait should be added. In addition, attention should be paid to eliminating water snakes and water rats. It is also essential to repair the escape-proof wall at any time.

4. Water quality management. The water quality of the crab pond must be kept fresh, so the water should be changed frequently according to the changes in water temperature. The higher the water temperature, the more frequently the water should be changed.

3. Can crabs be farmed with maggots?

Yes. (I am happy to answer your question. Please give me a good comment if it helps. Thank you!)

4. What are the secrets to breeding sea crabs?

A. Greenhouse conditions

The test greenhouse is a steel frame double-layer solar panel insulation greenhouse with an area of ​​1,200 square meters (20×60) and a water area of ​​1,000 square meters for seedling cultivation. It is equipped with aeration and oxygenation facilities and pipeline heating equipment. The greenhouse has a light transmittance of about 50% and is equipped with 5 200-watt incandescent lamps for nighttime lighting. In order to facilitate even feeding of feed, 3 sidewalks are set up.

B. Preparation before planting

About 10 days before seedlings are planted, add 30 cm of water and disinfect with 100 ppm quicklime emulsion. After 24 hours of disinfection, start the oxygenation facility to oxygenate. Next, add aquatic plants, mainly water peanuts. Soak the retrieved aquatic plants in high-concentration lime water or potassium permanganate solution for 24 hours, then rinse with clean water and evenly place them in the greenhouse.

The area of ​​aquatic plants is about 80% of the water area. Then gradually raise the water temperature to 20-22℃.

C. Stocking of crab seedlings

The crab seedling transport box should be placed in water for about 30 seconds, then taken out of the water, left for about 5 minutes, and then placed in water for 30 seconds. Repeat this process 4 to 5 times before placing the seedlings. Choose a place without aquatic plants, gently grab a handful of seedlings, and shake them slowly so that the crab seedlings can be evenly dispersed into the water.

Although the megalopa were transported for 3 hours, almost no megalopa died.

D. Daily feeding and management

In the early stage of crab fry entering the pond, they are mainly fed with tofu, fish paste, chimney worms and other baits. Use a 40-mesh mesh to filter the tofu into tiny particles, then add water and sprinkle evenly throughout the pond. Rinse the small fish and use a beater to make fish paste, then add 1% salt and water and sprinkle evenly throughout the pond.

The daily feeding rate is 100% to 150%, and the feeding is done 4 times a day, i.e. once before dawn, at noon, in the evening, and at midnight. The lights are turned on for 2 to 3 hours during the midnight feeding. When the crab seedlings have basically grown to the stage II juvenile crabs, the bait is mainly bean cakes and fish paste, and tofu is occasionally fed 1 to 2 times. The bean cakes are still made into small particles after being cooked. At this time, the feeding rate is controlled at about 100%, and the feeding is still done 4 times a day.

During this period, gradually add water to 0.5 meters. After the V stage, the feeding rate is 60% to 80%, and the bait is still mainly bean cakes and small fish. Feed 3 times a day, and no feeding at midnight. During the entire seedling raising period, observe the activities and feeding conditions of the crab seedlings, estimate the number and weight of the crab seedlings in the pond, and determine the reasonable feeding amount. During the period when the crab seedlings are concentrated molting, the feeding amount can be appropriately reduced, and the lighting time can be increased at night.

Daily management work mainly involves controlling water quality and regular disinfection. Every week, 5ppm lime emulsion is mixed with water and evenly sprinkled throughout the pond to add some calcium and maintain a pH value of 7.5-8.5; 50% stable chlorine dioxide 0.5ppm is used for disinfection every 10 days, and water is changed once every 15 days, with a water change volume of about 30%, and some new water is added appropriately, and the water level is controlled at 0.

When changing water, cover the inlet and outlet with 80-mesh silk to prevent seedlings from being discharged or other harmful organisms from entering. Keep the temperature difference within 5°C, and it is best if the water temperature is basically the same. Pay attention to the growth of aquatic plants in the pond and add some fresh aquatic plants in time.

E. Cultivation results

In short, the technical key to cultivating large-sized juvenile crabs in greenhouses is: selecting excellent seedlings, determining a reasonable stocking density, and strengthening daily management.