Culture methods and matters needing attention of crayfish in pond

With the continuous development of China's aquaculture industry, crayfish culture is becoming more and more common, especially in recent years, the midnight snack industry in China has been developing rapidly, and many restaurants specializing in lobster are on the rise. therefore, the demand of Xiao long Xiao is also increasing.

Culture methods and matters needing attention of crayfish in pond

1. Pond cleaning: the pond for raising crayfish requires adequate water source, good water quality, convenient entry and drainage, ridge top width of more than 3 meters, slope of 1:3, suitable area of 3 ~ 5 mu, rectangular, water depth of 1 to 2 meters. The newly excavated ponds and old ponds should be leveled, silt and sun-dried ponds should be removed according to the situation, so that the bottom and walls of the ponds have good water retention and reduce water leakage as much as possible. At the same time of cleaning the pond, the ridge around the pond is closed with a net 60-80 cm high, and the upper end of the net is also sealed with a plastic film of 20-25 cm, so as to avoid the entry of enemy creatures and the escape of crayfish later.

Crayfish are benthic reptiles, and the yield of the pond is not determined by the volume of the pond water, but by the horizontal area of the pond and the tortuous rate of the pond bank. In other words, the larger the horizontal area of the pond with the same area, the more the side length of the bank, the more shrimp can be released, and the higher the yield. Therefore, a 2'3-story platform can be built parallel with a net or bamboo mat near the ridge of the pond. The first floor is 20 cm below the water surface, 2'3 m long and 30'50 cm wide, and the distance between the two floors is 20'30 cm. Each platform has a slope leading to the bottom of the pool; a gap of 100 cm and 200 cm should be left between the two parallel platforms for crayfish to move to the shallow water. At the same time, a certain number of vertical meshes are set in the middle of the pond.

2. Pond cleaning disinfection: pond cleaning disinfection can effectively kill enemy organisms in the pond, such as catfish, Loach, snakehead, snake, rat, etc.; wild miscellaneous fish competing for food, such as carp, crucian carp, and pathogenic bacteria. The main methods commonly used are:

3. Quicklime disinfection: there are two kinds of quicklime: dry disinfection and water disinfection. Dry disinfection method: 50 kilograms of quicklime per mu, sprinkled in the whole pond, and then dried in the pond for 3-5 days, then filled with new water. Disinfection method with water: water depth of 1 meter per mu of water surface, 125-150 kg of quicklime dissolved in water, sprinkled evenly throughout the pool.

4. Bleach disinfection: after the bleach is completely dissolved, the whole pool is sprinkled evenly, the dosage is 20: 30kg per mu, and the amount of bleaching essence is reduced by half. Planting aquatic plants: crayfish have miscellaneous eating habits, and the aquatic plants eaten are eye vegetables, verticillium verticillata, water hyacinth, water floating lotus and water peanuts, etc. About 10% to 20% of the shallow water around the pond is planted with aquatic plants, which can be eaten by crayfish, providing an ideal place for shrimp to hide and perch, and a good place for crayfish to molt. "how small the shrimp is, look at the aquatic plants." the survival rate of raising shrimp in ponds with many aquatic plants is high. However, the planting area of aquatic plants should not be too much, otherwise the normal growth of crayfish will be affected by the excessive lush of aquatic plants and the lack of oxygen in the pond water at night. Generally, the planting area of aquatic plants should not exceed 1x5 of the total area of the pond. In addition, the bottom of the pond can be made of water grass into a haystack, every 5 meters put a pile, each pile of 5: 10 kilograms, sink at the bottom, put 20: 40 piles per mu. Each pile is tied with a rope, and the other end of the rope floats or is fixed on the water.

5. Influent fertilization: the water source requires fresh water quality, sufficient dissolved oxygen, no organic matter and industrial heavy metal pollution. When injecting new water into the pond, it should be filtered with 20-40 mesh gauze to prevent wild miscellaneous fish and fish eggs from entering the breeding pond with the flow of water. At the same time, fertilize and cultivate plankton to provide natural bait for young shrimp directly after entering the pond. To fertilize shrimp ponds, it is best to choose organic fertilizers, such as fermented organic grass manure. The application rate is 100,200kg per mu, so that the pool water has a certain amount of fertilizer, and the transparency of the pool water is kept at 35cm to 40cm.

What's a crayfish?

Crayfish are also known as procrayfish, red crayfish and freshwater crayfish. Shaped like a shrimp and a hard carapace. The adult is about 5.6 to 11.9 cm long, dark red, the carapace is nearly black, and there is a wedge stripe on the back of the abdomen. The young shrimp are uniformly gray and sometimes have black ripples. The claw is long and narrow. The middle part of the carapace is not separated by reticular voids, and there are obvious particles on the carapace. The forehead sword has lateral spines or scratches at the end of the forehead sword.

It is a freshwater economic shrimp, which is very popular because of its delicious meat. Because of its omnivorous, fast growth and strong adaptability, it forms an absolute competitive advantage in the local ecological environment. The range of food intake includes aquatic plants, algae, aquatic insects, animal carcasses, etc., and kill each other when food is scarce. Crayfish has become an important economically farmed species in China in recent years. In the process of commercial breeding, we should strictly prevent escape, especially into the inaccessible original ecological water body. It causes destructive harm to the ecological competitive advantage of local species.

Breeding and management of crayfish in paddy field

I. Feed feeding

Shrimp culture in rice fields should try to achieve timing, positioning, quantitative, qualitative feeding. Lobster eating habits are miscellaneous, meat (small fish, snail meat, river meat, fish, earthworms, animal offal, silkworm pupa), essence (sugar cakes, corn, wheat, barley flour), green (there are all kinds of aquatic grasses, vegetable scraps, etc.) feed. The daily dose is generally 4% to 6% of the body weight of shrimp. In the early stage, they were fed twice a day, once in the morning and once in the afternoon, and once at about 18:00 in the later stage.

II. Water and fertilizer management

After lobster stocking, field ditch management is a very important link. The water depth of the paddy field is maintained at about 20cm, and the water injection is generally carried out at 10lv 00Mel 11RU 00, keeping the water temperature of the diversion water close to that of the paddy field.

In the process of rice field management, the water level should also be regulated according to the requirements of rice drying and pest control. In the middle stage of rice growth, the field should be exposed properly, so as to increase light, root activity, sterilization and temperature. At ordinary times, we should also do a good job in flood control, drainage and escape prevention, and timely check whether the inlet and drainage and shrimp interception equipment are in good condition after a rainstorm to prevent shrimp escape.

III. Prevention and control of diseases and natural enemies

Adhere to the principle of giving priority to prevention and combining prevention with prevention. In the process of rice growth, it is necessary to spray pesticides to control pests, and fresh water should be replaced after spraying pesticides, so as to provide a necessary ecological environment for the growth of rice and lobster. High-efficiency and low-toxic pesticides were mainly used for rice disease control, spraying method was adopted to make the medicine fall on the leaf surface, and the suitable application time was 8-00-00-100-100 on a windless sunny day. If the enemy is found, it should be eliminated in time, and at the same time, a secret net should be placed at the outlet to prevent the enemy from entering.

Misunderstandings that should be avoided in crayfish culture

1. With regard to seedlings: at present, lobsters can also be called crayfish or Japanese crayfish, which are all of the same breed, and there is no "hybrid variety". Because the cost is too high and the natural seedlings are abundant and cheap, the artificial seedlings are still in the laboratory stage; in addition, do not mistakenly believe that lobsters are domesticated and kill each other less and buy lobster species at a high price from other places.

Many people think that as long as they invest in growing lobsters in the first year, they will get a good profit year after year through their own continuous reproduction. In fact, the output of lobster culture was the highest in the first year, and then decreased year by year. Due to the lobster life cycle of 16-18 months, coupled with inbreeding, functional degradation, disease resistance decline, the yield will be sharply reduced or even no harvest after 3 years.

2. On water quality: some people think that lobsters can also grow well in smelly ditches, but not both good and bad water can be raised. Fresh water quality is the key to the high yield of lobster farming. It is required that the coverage of aquatic plants in the pond should be 30%, 60%. The transparency of the water body is about 30cm, the dissolved oxygen content is more than 5 mg / L, the water should be changed regularly, each time the water is changed by 1 cm, and the water level is kept above 80 cm in high temperature season.

3. With regard to feed: lobster is a creature that is omnivorous and partial to animal bait, and its growth depends on the intake of protein. It can be mainly composed of fresh miscellaneous fish and field snails, supplemented with plant food, and can also be fed with compound feed with protein content of no less than 32%. Rotten animal and plant feed should not be fed because of its low utilization rate and easy to deteriorate the water quality.

In the process of crayfish culture, in addition to understanding the living habits of crayfish, it is also very important to master its culture technology, and crayfish are generally cultured in ponds, so in the process of crayfish culture, the environment of the pond is also very important.