Fertilization and feed
In the culture pond, some manure is first applied to cultivate plankton and provide bait for snails. The amount of fertilizer applied depends on the bottom material of the snail pond. After the snails are put into the pond, they are fed with vegetables, rice bran, fish offal or vegetable cakes and bean cakes. Green horn and fish viscera should be chopped and mixed with feed such as rice bran. Vegetable cake, bean cake, etc. Should be soaked and softened to facilitate the feeding of snails. The feeding amount depends on the feeding situation of snails, generally calculated as 1%-3% of the total snail, and fed once every 2-3 days. Feeding time every morning, feeding position does not need to be fixed, and feed is put every other day. When the temperature is lower than 15℃ or higher than 30℃, there is no need to feed.
Water quality regulation
First, the snail pond should be filled with fresh water frequently to adjust the water quality, especially in the breeding season. It is best to keep the pond water flowing, especially in high temperature season, and it is best to adopt running water culture. Micro-flowing water cultivation is the best in spring and autumn. The water depth of snail pond should always be about 30 cm. The second is to adjust the pH of water. When the pH value of the pool water is low, apply 0. 15-0. 18kg of quicklime per square meter and spray it every 10- 15 days to keep the pH value of the pool water at 7-8.
Overwintering management of snails
When the water temperature drops to 8-9℃, snails begin to hibernate. During hibernation, snails drill into the soil with the top of their shells, leaving only a round hole on the soil surface, and bubbles come out from time to time to breathe. Snails don't eat during the wintering period, but the water depth of the culture pond still needs to be kept at 10- 15 cm. Generally, change the water once every 3-4 days to maintain an appropriate oxygen content. After a year of careful breeding, the released young snails can reach 10 ~ 20g, and the hatched young snails can reach more than 5g that year.
When harvesting snails, we should adopt the method of catching large snails and putting small snails on the market in batches, and selectively eat adult snails, keep young snails and some female snails, so as to replant naturally and avoid releasing seedlings in the future. According to their living habits, in the hot season of summer and autumn, they choose to pick up bamboo branches and grass stems rotating on the shore or in the water body in the morning and evening; In winter and spring, choose sunny noon to pick. In addition, snails can also be harvested by catching them in the lower pool or picking them up in the drainage dry pool. Snails are very simple to transport, and can be packed in ordinary bamboo baskets and wooden barrels. , or packed in woven bags. As long as snails stay wet during transportation, they can avoid exposure to the sun. Choose a snail pond with sufficient water, running water and no pollution. Generally, the pool is 1.5 m wide, 10~ 15 m long and 30~50 cm deep. A dike with a height of 20 cm is built between the two ponds for walking, and the bottom of the pond is paved with 10 cm thick mud. Aquatic plants such as Zizania latifolia, asparagus, water hyacinth and duckweed can be sparsely planted in the pond, which can not only shade, but also climb, provide bait for snails and improve the utilization rate of snail pond. 60~80 cm high fence or mesh fence should be built around the snail pond.
Most snails breed naturally. Artificial culture can be picked up from paddy fields, water bamboo fields and muddy ditches, or bought in the market, and then fresh snails with light brown color, thin shell and blunt tail are selected as seed snails. Snails with average body weight 1.5 ~ 25g reach sexual maturity and can reproduce above 1.5℃. The female is big and round, while the male is small and sharp. With the development and utilization of local varieties, snail farming has been developed in recent years. Oncomelania belongs to mollusks, gastropods and snails, and there are four kinds of snails, namely, China Oncomelania, China Oncomelania and Wusuli Oncomelania. The main cultured species is Ampullaria gigas. River snails are generally suitable for breeding in rice fields, shallow ditches, low-lying areas and wetlands. Snails have low requirements for breeding sites. Generally, it can be cultivated in shallow water with a little improvement. It can be cultivated in soft mud bottom water containing a lot of humus, and it is best to have certain micro-flow conditions. So far, there are few diseases and insect pests of snails found and reported.
Here are some suggestions for your reference: hibernation. Attention should be paid to preventing high temperature in summer, because the water in rice fields is shallow, and the water temperature in summer may reach the upper limit lethal temperature; However, the content of organic matter in mud bottom should not be too high in winter, otherwise it will easily produce toxic substances and affect the overwintering of Oncomelania hupensis. Sensitive, normal life requires dissolved oxygen in water to be above 4 mg per liter. When it drops to 3.5 mg, the appetite will decrease, and when it drops to 1.5 mg, people will die. Carp feed. Pesticides, and should be used in sunny days; Suitable for half use in rice fields. Hirudo, loach and Monopterus albus are mixed, which has better economic benefits. There are 100~ 120 seed snails per square meter, and 4 summer pomfrets can be raised in the pond. Before releasing the snails, apply a proper amount of manure in the pond to cultivate the bait organisms. After releasing the snails, feed the leftovers such as vegetable leaves, rice bran, bean cakes, vegetable cakes and animal offal. Feed the cake after it is soaked soft, and chop other feeds and mix well. The feeding amount is generally 1%~3% of the total weight of snails, and it is 1 time every 2~3 days, and the feeding amount is adjusted according to the growth and feeding situation of snails.
Oncomelania diseases are few, and daily management focuses on managing water and preventing ducks, cats, snakes, rats and birds from entering the pool to prey on Oncomelania, so as to prevent Oncomelania from fleeing. Snails should be cultured in shallow water and flowing water, and the depth of pool water should be 25~30 cm, especially in breeding season and high temperature season. Snails have strong adaptability and few diseases. As long as a large number of pesticides and fertilizers are avoided, many flat rivers, streams, potholes, paddy fields, ponds and other ordinary water bodies in rural areas can be stocked. If you dig a special pond for feeding, choose a place with convenient water source and humus soil to build a pond (if the soil is not suitable, it is best to apply mixed compost to improve it first). Keep the sediment thickness 10 ~ 15cm, and the area is not limited. If it is an open water body, a small amount of duckweed and water lily can be planted on the water surface, some vines and melons and vegetables can be planted around the pond for shade, and bamboo tails, branches or stones and grass can be arranged in the water for snails to live in seclusion.
10 snail enters tang qian, and quicklime is applied to the whole pond at a dosage of 50 ~ 100 kg per mu to remove wild fish, shrimp and other miscellaneous snails. After 3 ~ 4 days, organic fertilizer and culture bait organisms are piled up in the water for snail to eat. Extensive farming in natural water can meet the growth needs of Oncomelania snails as long as the fertility of water body is maintained and appropriate organic fertilizers such as manure, chicken manure, cow dung, pig manure or straw are applied regularly. In the case of high-density intensive farming, artificial bait must be put in. Snails don't need much nutrition. Rice bran, wheat bran and soybean powder were simply mixed at the ratio of 60%, 25% and 15% to make the first-class feed for snails.
According to the feeding situation and climate conditions of snails, snails have a strong appetite at a suitable temperature (that is, 20 ~ 28℃), and can be fed once every two days, and the feeding amount is 2% ~ 3% of their body weight each time. When the water temperature is in the range of 15 ~ 20℃ and 28 ~ 30℃, feed it twice a week, and the dosage is about 1% each time. When the temperature is lower than 15℃ or higher than 30℃, it is less than or equal to zero.