Earth Pond Crab Cultivation Technique
The cultivating seedlings of crabs in the earth pond is the technical method of artificially breeding crab larvae in excavated earthen ponds. Because of its low input costs and simple operation, it has been adopted by a large number of crab farmers. The main technology is introduced as follows for reference. Cultivation pond conditions Cultivation ponds should be located near water sources, with sufficient fresh water, clean water, convenient drainage, power supply, and convenient transportation. The pool is solid and the slope ratio is 1:3-1:4. It is better to cover the slope with a layer of plastic film, then add 20 cm of soil and compact it. The bottom of the pool is flat and slightly inclined toward the outlet end. 1-1.5) 667 square meters is appropriate, the water depth is 1.0-1.5 meters. Around the pond, a thick plastic film is used to build escape-proof walls. It is buried 10 centimeters below the ground. The height of the wall is 60 centimeters. Every 1.5 meters to 2.0 meters is fixed with wooden sticks or bamboo rods. The water inlet and outlet are covered with polyethylene mesh cloth. To prevent crabs from escaping when lodging and entering the drain. The pool should be equipped with mechanical and electrical equipment such as pumping and oxygenation. Qingchi disinfection Crab seedlings 15 days to 20 days before entering the pool, drain the pool water, and expose the bottom of the pool for several days. Use the quicklime dry method to clear the pond. The dosage is 80kg -100kg/667m2. The method is to add the water-soluble and heat the whole pool to spray evenly. , leaving no dead ends. The next day, the silt is used to turn the sediment to fully mix the lime slurry with the sediment. This will not only kill the wild fish, predators, and pathogens, but also improve the sediment and increase the calcium ion content in the water. It is conducive to the growth and development of juvenile crabs. Water fertilization Before the crabs enter the pool, 7 to 10 days before entering the pool, water is poured into the pond for 50 centimeters, and the livestock and poultry manure after fermentation is disinfected (preferably chicken manure is used), and the amount applied is 200-300 kg/667 square meters. Tongkou, which has a relatively good water quality, can be reduced to 100-200kg, and Xinkaitang can be increased to 300-400kg. 2 days to 3 days after the application of EM bacteria, unicellular algal activin, etc., in order to enhance the effect of fertilizer and water, water purification, 7 days later there is a large number of rotifers in the pool, Cladocera, copepods and other plankton breeding, Provide natural bio-feeds for crabs that will enter the pool in the future. Crab stocking Crab quality requirements are relatively neat specifications, body color is light yellow or ginger, shiny and transparent sense, the individual stout, lively swimming, crawling agile, feel micro-thorn, microscopic examination of the body no bacteria, no poly surface tapeworm and Other foreign objects. Grab a handful of crab that has been drained, gently grasp it, and release it. If the crab quickly crawls away and flees, it means that the quality of the crab is better. Otherwise, the quality is poor. The stocking size of crabs should be determined based on factors such as pond conditions, feeding conditions, out of specification, and management level. The general stocking size is about 150,000/kg, and the stocking density is 1.5kg - 2kg/667m2. The batches required to store the crabs in the same pond should be the same and their specifications should be the same. Feeding management There are two types of bait crabs, natural and artificial. Natural foods include plankton, aquatic plants, and benthic organisms; artificial diets include compound feeds and wheat, vegetable cakes, bean cakes, and pumpkins. Crab seedlings from under the pond to the molting metamorphosis for the first phase of crabs in the pool of plankton as food, can increase when the lack of milk, surimi, cooked egg yolk, etc., adhere to many times a day feeding, and to do less many. During the period of I-V larvae, artificial baits or compound feeds are mainly used. During the period of I-III larvae, the daily feeding amount is 80%-50% of the total weight of the crabs, and during the period of III-V larvae crabs The amount fed was 30% to 10% of the total crab weight. Feed the bait in shallow water or on aquatic plants and other attachments by means of feeding around the pool. Every day from 7:00 to 8:00 in the morning and from 6:00 to 7:00 in the evening, feed 1 to 30% to 40% of the daily feed in the morning and 60% to 70% of the daily feed in the evening. Water quality management When the crabs were just under the pond, the water depth was maintained at 30 cm to 40 cm. The shallow water in the pool was warmed up by the light and was conducive to the propagation of natural biological baits, which was conducive to the growth and development of the crabs. When the crab shell metamorphosis as stage I crab, add water 5 cm, metamorphosis for stage II crab, the same water 5 cm, metamorphosis for stage III crab, add water 10 cm -15 cm. Using staged water injections can force the crabs digging holes under the waterline to search for food in order to prevent lazy crabs. During the cultivation process, if the water quality is found to be deteriorating, the water should be changed in time; in case of heavy rain, the high water level should be set appropriately to cause sudden changes in the water quality of the water, causing dead seedlings. Apply 60 mesh mesh filter when adding water to prevent enemy pests from entering the cultivation tank. Crab seedlings are intensively bred for 20 days to 30 days. After the oyster shells have been used 3 to 5 times, they grow into larvae with specifications of up to 10,000/kg - 20000/kg. Individuals have the size of soybeans, so they are also called production. V young crabs or crabs may be caught in another pool for larval rearing or directly used for crab breeding. Garden Hose Cart,Garden Hose Reel Cart,Portable Garden Hose Reel Carts,Heavy Duty Garden Hose Reel Cart NINGBO QIKAI ENVIRONMENTAL TECHNOLOGY CO.,LTD , https://www.hosereelqikai.com