First, the economic value of snails

Snail meat is tender, nutritious and delicious. The protein content of its meat is higher than that of chicken, duck, pig, cow and mutton, and it contains almost no cholesterol and low fat. Snail protein is rich in 20 essential amino acids and many other nutrients, such as calcium, phosphorus, iron, thiamine, glucose, liver sugar and other carbohydrates. It can be considered that the food made of snails is a kind of highly nutritious food.

Snails, as medicinal animals, can also be used as medicine. Shellfish can be used as medicine, clearing away heat and toxic materials, relieving asthma and regulating hernia, and is mainly used to treat thief wind, eccentricity, traumatic injury, proctoptosis and epilepsy. Snail enzyme can be separated from the digestive gland of snails, and it consists of more than 30 bioactive enzymes, such as cellulase, hemicellulase, mannanase, sucrase, lactase and proteolytic enzyme. Snail enzyme can be used in genetics and cell biology research, and can also be widely used in light industry, textile, fermentation and brewing, nutrition and health care, cosmetics and other industries. Snailase was isolated from Oncomelania hupensis from China 65438-0974.

Snail viscera and shells account for 20% ~ 30% of body weight. In the process of processing, these unqualified scraps can be made into feed, and their nutritional components are also quite high, and the crude protein content also reaches 60.9%, which is close to Peruvian fish meal.

Second, the current situation and prospects of snail farming

Snail farming has been from wild to artificial farming for more than 100 years. Snail farming abroad has been industrialized, and related industries are also very developed. There are manufacturers specializing in the production of cages and other appliances. The artificial breeding of snails in China began in the 1960s and became the most popular in the 1980s. At present, it has become mature and developed. Calm down from speculation and planting, no longer blindly develop, but develop into deep processing and comprehensive utilization, and gradually embark on a virtuous circle.

China snail industry is in the forefront of the world in artificial breeding technology, food, comprehensive utilization technology and the development of new products by using high technology. At present, there are nearly 300 units engaged in snail development, scientific research, processing and trade in China, including more than 50 snail cannery, pharmaceutical factory and daily chemical factory. The main products are: "Kiwifruit King" drink, "White Jade King" drink, "White Jade Acacia Dew" drink, snail tremella juice, Chinese soft-shelled turtle jade essence, super skin care water, Baochunling nutrient solution, white jade shampoo, female series nutrient solution, natural snail paste, healthy oral liquid, Oled nutrient solution, rehabilitation nutrient solution, white jade fruit milk, white jade snail jujube sausage and other snacks, canned snails with clear water and wild delicacies.

China's snail breeding conditions are superior, suitable for the growth of snails from south to north and from east to west. At the same time, snails can sleep for 6-8 months without adapting to the growth conditions, and the feed sources are very extensive.

However, there are still some problems to be solved urgently in snail farming: the scale is small, the processing and farming are seriously out of touch, the farmers have raised it, and the products don't know where to sell. On the other hand, the processing factory can't get enough supply; With the development of high-density aquaculture, the intensity of quarantine and disease prevention is not enough, which leads to the spread of some diseases in a large area and is difficult to control, and the treatment methods of some diseases have not developed, which leads to the helplessness of seeing the onset; Gene breeding can't keep up, and some enterprises don't even have basic seed selection measures; Serious pollution, pollution here means that the feed eaten by snails is polluted, which leads to the meat quality exceeding the standard in heavy metals, pesticides, etc., and it is difficult to enter the international market, thus hindering the further development of snail breeding.

Third, the biological characteristics of snails

Snails belong to mollusks, Gastropoda, Spirogyra, Umbrella, hermaphrodite and terrestrial shellfish. There are more than 25,000 kinds of snails in the world. Snail shells are spiral and vary greatly in size. They can be divided into pagoda, gyro, sphere and cone in shape. Snails in ancient times lived in water and gradually developed into land. Degenerate gills form a vascular network on the inner wall of the mantle, and rely on the body to secrete mucus instead of water for gas exchange, and then evolve into lungs and become modern snails.

Snails have almost all muscles and no bones. There is an elastic muscle under the body that is the most developed, and other parts are made up of small muscles, which move by the constant expansion and contraction of muscles.

Fourth, the characteristics of snail farming

1. The initial investment of snail culture is small.

Snail breeding generally uses idle houses, caves, burrows, etc. to build three-dimensional shelf breeding boxes, which are 1000 cm long, 500 cm deep and 250 cm high, and need to invest 5 ~ 10 yuan, and can feed 100 snails and 3,000 ~ 5,000 small snails. After snail farming is put on the line, less investment is made in other later stages. Snails have a small appetite and a wide range of feed sources. The main concentrate is rice bran, wheat bran and corn flour. Green feed includes roots, leaves, flowers and fruits of plants. Snails like fresh and juicy green feed, such as watermelon skin and Chinese cabbage.

Snails have strong vitality and are easy to raise.

Snails are easy to raise and manage. Generally, they are junior high school graduates. They can be raised with diligence and low labor intensity. Oncomelania hupensis has strong vitality, and its morbidity and mortality are generally below 1%.

Five, snail breeding technology points

1. temperature 16 ~ 40℃, the optimum temperature is 25℃, generally high or low. Heating must be carried out by earthworm fire path, and it should be prepared all year round, especially in late spring and early autumn, to prevent sudden flooding. Conditional heating is the best, and it is not necessary to use a stove for heating.

2. humidity. The soil surface humidity of the feeding soil should be kept at 25% ~ 35%, and the relative humidity of the air should be 85% ~ 90% to make it moist, and the top should be covered with plastic sheets for moisture control and moisturizing.

3. In order to prevent dry air and cold air from blowing in directly, double doors, cloth hanging and wind deflector should be adopted for import.

4. Resolutely control the malodorous gas entering the breeding ground.

5. Feeding soil must be controlled at pH 6.5 ~ 7.5, and it is forbidden to use polluted sand containing pesticides and chemicals.

6. The culture container must have good water permeability and air permeability.

7. Don't be exposed to bright light when not working, preferably in the dark. Lighting with 15W red bulb at night can stimulate spawning.

8. Hatching of eggs. The key to the success or failure of snail farming lies in the hatching of eggs. Indoor temperature is controlled at 20 ~ 25℃, air humidity is controlled at 90% ~ 95%, and soil surface humidity is controlled at 25% ~ 30%. Improve the method of egg collection and incubation, and adopt the 60-day snail cultivation method. This method can greatly improve the reproductive efficiency of snails, and the general hatching rate is above 95%.

9. The feeding of young snails is related to the success or failure of the rapid development of snail quantity and output, and special attention should be paid to the control of temperature and humidity. Generally, the temperature should be controlled between 25 ~ 30℃, the water content of the soil is 30% ~ 35%, and the relative humidity of the air is 80% ~ 90%. Eat more fresh and juicy feed, supplemented by calcium supplements.

10. 1 ~ 3-month-old snail culture ponds should be humidified and do not splash water. Spray with a sprayer, preferably warm water.

1 1. Remove dead snails in time.

12. It's best to kill two birds with one stone when earthworms and snails are mixed.

13. Prevent the invasion of natural enemies and kill rats and ants. Regular spraying with11000 trichlorfon solution can effectively kill the largest natural enemy mite of Oncomelania hupensis, and regularly disinfect the snail breeding ground with peracetic acid diluent to kill pathogenic microorganisms.

14. The lowest cost and best feed formula: 50% rice bran, 40% shells, 8% yeast powder and 2% others.

Six, white jade snail feeding technology

White jade snail, commonly known as white meat snail.

1 living environment

White jade snails, like other snails, like to live in a dark, humid, loose and humus-rich environment. They are afraid of light, heat and direct sunlight. Very sensitive to the environment, when the humidity and temperature are not suitable, the snail will retract its body into the shell, secrete mucus to form a protective film and seal the shell mouth to overcome the interference of bad environment. When the environment is suitable, it will automatically dissolve the protective film and start activities again. Therefore, we should pay attention to the influence of temperature and humidity in the process of breeding.

Suitable temperature 16 ~ 30℃, humidity 60% ~ 85%, soil humidity about 40%, pH 5 ~ 7. When the temperature is lower than 15℃ and higher than 35℃, it sleeps and stops growing and reproducing.

2. Feeding habits of white jade snails

All kinds of green plants and bran can be used as food. Generally, broadleaf plants such as Chinese cabbage, green vegetables and lettuce are fed in spring; In summer, you can feed a lot of sugar cane, sunflower leaves, all kinds of fruits and skins, etc. In autumn, the temperature is low and the food intake is reduced. You can feed some leaves and chips. White jade snails do not eat grass and weeds, and refuse to eat pungent onions, leeks and garlic.

In order to speed up the growth rate and improve the spawning rate, it is best to add 10% ~ 15% concentrate such as wheat bran and bean curd residue to the feed, but its digestibility is weak and it is difficult to feed concentrate rich in starch such as wheat flour and rice flour. Mineral feeds such as stone powder and shell powder can also be added to the feed to meet the needs of snail growth. Concentrated feed should be crushed, fruits and tubers should be cut into pieces before feeding, and attention should be paid to the diversity of food to prevent anorexia. Feeding should be done in the evening and water should be sprayed before feeding.

breed

White jade snails are hermaphroditic and cross. Artificial farming can breed all year round as long as the temperature and humidity are suitable. It usually takes 6 months from hatching to sexual maturity, and eggs can be laid in caves within 15 ~ 20 days after mating and fertilization. Eggs are the size of mung beans and covered with a shiny white film. Every time 100 ~ 200 eggs are laid, young snails can hatch in 8 ~ 15 days, and the life span is generally 5 ~ 6 years.

The incubation temperature is 20 ~ 30℃ and the humidity is 80% ~ 90%. If there is sludge and feces on the eggs, there is no need to scrub them, because there is a protective film around the eggs to prevent the invasion of bacteria and microorganisms. Put the eggs into the pot, put the soil on it, flatten it with the soil with the same humidity as the feeding soil, evenly discharge the eggs, cover the spout with a wet cloth, and then seal the spout with a film. After 8 ~ 15 days, if the young snail is still outside the shell, it is a failure.

4. Feeding management (1) feeding mode

According to the farm site and equipment, it can be generally divided into outdoor open and indoor closed. You can dig outdoor ditches or build greenhouses. If ditch planting is adopted, the ditch should be built in the leeward and sunny place, with a depth of 50 ~ 70cm and a width of 2 m. The length depends on the number of breeding. The ditch should be high on one side and low on the other, with a slight slope, and covered with film and bamboo curtain to prevent the escape and injury of natural enemies such as frogs and birds. Indoor culture can be carried out in clay pots, plastic boxes, wooden boxes, cement pools, etc. And sealed with sand cover, wet cloth, film, etc. In order to moisturize and prevent rats.

(2) Preparation of feeding soil

Feeding soil should be moist, loose and fertile. It is best to choose unpolluted pastoral soil and yellow sand, add a small amount of stone powder to mix, and disinfect and sieve after 3-5 days of sun exposure. The earthwork proportion is: fine soil 30%, sandy soil 30%, yellow sand 20%, cinder ash 15% and stone powder 5%. After adding water, the humidity is about 40%, that is, once they are held together, they will disperse when they are blown. The soil thickness in the basin is divided into: adult snail 10 cm, adult snail 7 cm and young snail 3 cm. Change the feeding soil 1 time from 0 to February.

(3) Feeding methods. Young snails should be fed with fresh leaves and some concentrated feed. The temperature is not lower than 20℃ and controlled at 25 ~ 30℃. Don't spray young snails directly when spraying water. Food containing calcium in feed must not be lacking. After 1 month, it is transferred to the adult snail culture basin, and the stocking density changes from dense to thin with the continuous growth of individuals. Stocking 400 ~ 500 heads per square meter, and stocking 200 ~ 250 heads before harvest. A 60×30×25 cm feeding box can keep 65,438+000 animals. After 5 ~ 6 months, when the shell is 4 cm high and weighs 40 grams, it can be harvested.

Seven, Oncomelania hupensis overwintering management points

In addition to wintering naturally in the southeast coastal areas of China, artificial cultured snails must keep warm in winter to ensure the safe wintering of snails. The practice is to strengthen nutrition before the temperature drops to 15℃ and let it eat well. When the temperature is lower than 15℃, move the snails cultivated in the wild into indoor pools and boxes. Feeding soil can be thickened to more than 25 cm. Or, after the snails form a film and seal the shell opening, the shell opening of each snail faces down and is arranged in layers closely, with the spacing between each layer being about 5 cm, and the top layer of the snail is covered with soil 10cm thick, so as to carry out high-density wintering. The water content of the overwintering soil should be low, not exceeding 10%, and no or less water should be sprayed at ordinary times. Earthworms in the wintering soil should be removed to prevent snails from entering the shell mouth and dying. If the temperature of the wintering pool can be kept above 5℃, it can be safely wintered.

Modern practice shows that keeping a certain temperature and humidity in the feeding room and providing sufficient feed through artificial measures can not only relieve the hibernation of snails, but also achieve the purpose of breeding in winter. A stove can be used in the feeding room, an iron chimney is connected to the stove, and the chimney goes out of the room after circling the feeding room to make a complete set of heat preservation equipment, and the room temperature can also be maintained by electric heaters, glass greenhouses, greenhouses and other heating methods. According to the actual situation, heat preservation measures with low cost and good effect can be adopted. The room temperature of the feeding room should be controlled between 20 ~ 30℃ and not lower than 65438 05℃. In the temperature-controlled feeding room, there is a certain temperature difference in different places, and the temperature near the heat source is high, so the young snails can turn to the area with higher temperature. The water in the greenhouse evaporates quickly, so we should pay attention to changing water and sprinkling water. You can often put a pot of hot water to evaporate and improve it.