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How to raise crayfish indoors?
Key points of crayfish culture and high quality seedling raising

Parent shrimp can be selected from September to June of last year 10, or from March to April of that year. Individuals over 0/0 month old, weighing 30-50g, with complete appendages, strong physique, no disease or injury, smooth body and strong mobility should be selected, and the ratio of male to female shrimp is 2: 1 or 65438. Male and female crayfish have obvious characteristics in appearance and are easy to distinguish. ① Among the sexually mature Procambarus clarkii, males of the same age are obviously larger than females; ② For shrimps with similar body length, the male paws are thick, and there are bright red soft warts on the outside of both ends of the paws, while the female paws are relatively small, and there are no soft warts on the paws, even if they are colored, they are pale; (3) The male shrimp's reproductive hole is located at the base of the fifth foot, and the female shrimp's reproductive hole is located at the base of the third foot; ④ The abdomen of sexually mature female shrimp is enlarged, while that of male shrimp is relatively narrow.

Parent shrimp cultivation Parent shrimp cultivation ponds generally adopt soil ponds, and the area depends on the scale. Small-scale production can range from a few square meters to dozens of square meters; Mass production is generally more than 80 square meters, and the highest can reach more than 2000 square meters. The depth of the pool is 0.5m ~ 1m, and the width of the ridge is more than1.5m. Build water intake and drainage system, and build an escape wall around the ridge of the pool with plastic film or calcium plastic plate. The water source is abundant, fresh and pollution-free, and the dissolved oxygen is high, especially in the intensive cultivation period, the dissolved oxygen in the water should be above 4 mg/L, and some small ditches should be dug in the pond to facilitate the operation when collecting shrimp seedlings. Before/0/5 days of parent shrimp stocking, the whole pond is sprayed with quicklime/0/50kg of kloc every 667m2 for disinfection, and 500-800kg of decomposed livestock manure is applied to improve the water quality. Then filter and inject fresh water, put hidden objects such as branches, roots and bamboo tubes for shrimp to climb and inhabit in the pond, and transplant some aquatic plants. The area of aquatic plants accounts for about 1/3 of the area of the aquaculture pond. The stocking density of parent shrimp should be appropriate. Usually, the parent shrimps leave ~10kg ~150kg/667m2 in September. Parent shrimps selected from March to April are stocked at 80kg ~ 100kg per 667m2. Before stocking, the shrimps were soaked in 3% salt water 10 minute to kill pathogens. During the breeding period, it is necessary to strengthen feed feeding, such as feeding fresh aquatic plants, bean cakes, wheat bran or compound feed, and adding some animal feed, such as crushed snail meat, livestock and poultry slaughter leftovers, etc. Daily feeding amount: 2%~3% of the parent shrimp's weight in March, 4%~5% in April, 6%~8% in May, 1 time in the morning and evening, mainly in the evening, accounting for 70% of the daily feeding amount. At the same time, strengthen water quality management, generally change water every 18 days to 15 days/time, and change pool water every time 1/3; Every 20 days, sprinkle 20-25 grams of quicklime 1 time per cubic meter of water in the whole pond to promote the gonad development of the parent shrimp.

After breeding and hatching for 4-5 months, when the water temperature is above 65438 08℃, the parent shrimps begin to mate. Male shrimp excretes sperm into the seminal vesicle of female shrimp, and fertilized eggs hatch on the hairs of the abdominal appendages of female shrimp to form young shrimp. The suitable incubation temperature is 22℃~28℃. When the water temperature is 18℃~20℃, the incubation period is 30 ~40 days, and when the water temperature is 25℃, it only takes 15 ~20 days. The growth and development of young shrimp after hatching is completed under the protection of the mother. As soon as the young shrimp leave the mother's body, they can take the initiative to eat and live independently. When a large number of young shrimps are found in the culture pond, they should be collected in time.

The cement pond with an area of 20 ~ 40m2 and a water depth of 0.6 ~ 0.8m is the best pond for shrimp fry cultivation. You can also choose a soil pond with an area of 667 square meters to 2,000 square meters, a slope ratio of 1:2 and a water depth of 0.5 meters to 1 meter, which requires sufficient water, good water quality, convenient water intake and drainage, and anti-escape facilities. Then, 500 kilograms of decomposed human and animal feces are applied every 667 square meters to cultivate natural bait that young shrimps like to eat, such as rotifers, cladocera, copepods and other plankton. In addition to roots, bamboo tubes and other things, a certain number of submerged and floating plants should be put in the pond to provide climbing habitats, molting and hidden places for young shrimps. The stocking quantity of young shrimps is generally 0/50 ~ 230 per square meter/kloc-0, with the same specifications, and the shrimps are released in sunny morning or cloudy day. After stocking 1 week, ground soybean milk can be fed 3~4 times a day; The second week, small fish and shrimp, snail meat, earthworms, silkworm chrysalis and other animal feed. Mainly feed paste feed made of corn, wheat and fresh plant stems and leaves, and mix and crush them properly. Feed 1 time in the morning and evening, and 70% of daily feed is fed in the evening. In the early stage, the daily feeding amount was 0.25 kg ~0.40 kg per 10,000 young shrimps, and then it was about 10% of the shrimp weight in the pond. During the culture process, change the water 1 time every 7 days to 10 day, and change the pool water 1/3 every time to keep the dissolved oxygen in the pool above 5mg/L; Every 20 days or so, use 20g quicklime to spray water 1 time in the whole pond, so as to adjust the water quality, increase the content of free calcium in the water and provide the calcium needed by young shrimps when molting. After 25 ~30 days' cultivation, the young shrimp can grow and molt for 5~8 times, and its body length can reach 3 cm.

Five problems in crayfish culture

1. What are the requirements?

A: Crayfish has strong adaptability to the environment and can grow in lakes, ponds, river ditches, rice fields and other water bodies. The water source should be sufficient, and the water depth is about 1 m.

2. Can crayfish be kept in the goldfish bowl?

A: Yes, but it can't form large-scale farming and can't produce economic benefits.

3. What are the advantages of keeping crayfish?

A: Generally, 30 kg of shrimp can be raised per mu, and 200 ~ 300 kg of crayfish can be raised, with a net profit of about 1000 yuan. After five or six years, even without shrimp, the yield per mu can reach 200 Jin.

4. When to start raising shrimps and where to buy shrimps?

A: Generally, shrimps are released in September every year, and caught and listed in May and June of the following year. It is best to buy shrimps nearby and choose crayfish with big heads and hard shells. Shrimp sources are in short supply this year, so farmers who are interested in raising crayfish can buy shrimps in advance and keep them in captivity until September.

5. If crayfish culture is widely promoted now, will it do harm to ecology and flood control?

A: Crayfish is not destructive. First of all, it needs to grow and reproduce in a specific environment; In addition, in aquatic products, the reproductive ability of crayfish is not the strongest, and a mother shrimp can breed 200 crayfish. At present, the export and domestic demand of crayfish are still in short supply. Even if no one eats it, crayfish are easy to catch and will not pose much threat. In addition, although crayfish like to dig holes, the test found that the depth of this hole is only twenty or thirty centimeters, and the highest one is only over one meter deep, and it is diagonally along the direction of groundwater, which will not pose a threat to flood control.

Industrial artificial propagation of freshwater crayfish

The indoor cement pond was established for the industrial reproduction of freshwater crayfish fry, and the method of running water or aeration combined with regular water change was adopted to provide a good environment for the growth and development of shrimp fry, which can be used for high-density seedling raising. Sufficient shrimp fry can be provided regularly according to the fry needed for aquaculture production.

First, nursery facilities. Factory nursery facilities mainly include: indoor incubation pond, nursery pond, water supply system, gas supply system and emergency power supply equipment. Conditional seedling plants can also build indoor temporary parent shrimp breeding ponds and mating egg ponds. The area of culture pond and nursery pond is generally 12-20 square meters, and the water depth of pond is about 1 meter. There are water supply and drainage systems and gas supply facilities, and it is best to use plastic products for water supply and drainage pipes. The construction scale of aquaculture ponds and nursery ponds should be determined according to the production scale of the unit and the market demand of shrimp seedlings in the surrounding areas.

2. Stocking and larval hatching of spawning shrimp. Parent shrimps used for industrial seedling raising are eggs-containing shrimps collected from ponds, lakes or reservoirs; You can also choose the parent shrimps collected in autumn, intensively cultivate them in the soil pool and then naturally mate and lay eggs in the pool. The fertilized eggs are basically the same in color and hatched in batches to ensure that the hatched larvae are basically synchronized, thus ensuring that the specifications of shrimp seedlings are basically the same. The eggs-holding shrimp can be directly put into the incubation pond or put into a cage in the incubation pond, and the mesh size of the cage can allow the shrimp seedlings to pass through and directly enter the incubation pond. The stocking amount is about 0/00 eggs per square meter/kloc. The eggs-holding shrimp hatched into flea-like larvae, which hung on the abdominal appendages of the parent shrimp and molted to form 1 juvenile shrimp. When the juvenile shrimp is within 1 cm, it is protected by the parent shrimp, which generally protects the juvenile shrimp for one week. Therefore, it is necessary to catch the empty parent shrimp in time. Young shrimps are scattered at the bottom of the pond, leading a benthic life and cultivating shrimp seedlings. Alternatively, you can incubate the eggs-containing shrimps in the culture pond, then catch and fish out the young shrimps with nets and disperse them in the nursery pond for culture. 20,000-30,000 young shrimps per cubic meter of water are moved to a nursery pond for culture. Young shrimps can be collected by lighting, running water trapping or drainage cage, etc., and the movements should be light and fast in the process of seedling collection and transplanting, so as to avoid injury to young shrimps and affect their development and survival rate.

Third, shrimp seedling cultivation. After hatching, the young shrimp will start eating soon, and then they can be fed with bait. The bait is mainly natural zooplankton and artificial bait. Natural zooplankton are mainly rotifers, larvae and copepods, which can be fed 1 time in the morning and afternoon respectively; Artificial bait is mainly cooked fish and mussel pulp and granular bait, which is fed 2-4 times a day, and the feeding amount depends on the activity, feeding and development of young shrimp. During the nursing period of parent shrimp, adult shrimp should be properly fed, and more water should be changed to maintain a good water environment. The whole seedling raising process needs 24-hour continuous ventilation.

Fourth, catch and raise separately. After the young shrimps leave the mother body, they are cultured in water with the water temperature of 20-25℃ for more than 10 days, and can be caught when they grow to more than 2 cm, and then they are cultured as young shrimps or directly as adults.

Cage culture technology of freshwater crayfish

In recent years, with the continuous expansion of freshwater crayfish culture area and the sharp decrease of wild resources, there is an abnormal shortage of fry. After years of exploration and research, the author summed up the cage culture technology of freshwater crayfish, which is introduced as follows.

1. Pond conditions: The aquaculture pond should be located near the water source, with convenient irrigation and drainage and quiet environment. The water quality is clean and pollution-free, and the transparency is 30-50 cm. It covers an area of 3-5 mu and is rectangular. The height of the ridge is 1.5m, and the average water depth is1.2m. The escape prevention facilities are made of calcium-plastic plates with a width of 60 cm, which surround the pond and the bottom is buried about 15 cm.

2. Structure and setting of the cage: The cage is made of 20-40 mesh (or screen wire), with a length of10m and a width of 3-5m. A calcium-plastic plate with a width of 15cm is sewn on the cage along the inside of the mouth to prevent the parent shrimp from escaping. The bottom of the tank is 10- 15 cm away from the bottom of the pond, and a cage is set near the water inlet of the pond to ensure the full exchange of water in the tank. A bamboo trellis is arranged right above the cage, and the bamboo trellis is covered with a black sunshade net.

3. Transplanting aquatic plants: transplanting Alternanthera philoxeroides around the pond, and planting Elodea and Kuroshio in the middle. The area of aquatic plants accounts for 50-60% of the total water surface of the pond. The area of aquatic plants in the cage accounts for 70-80% of the whole cage area.

4. Selection and stocking of parent shrimps: choose individuals who are over 10 month old, weigh about 30g, have bright and shiny body color, smooth body surface without attachments, normal body shape, strong physique, no diseases and injuries, complete appendages, hard carapace and strong vitality as parent shrimps. The ratio of male to female is 2-3: 1. Parent shrimps are stocked from August 20th to September 20th every year. Soak the parent shrimp in 3% salt water for 2-3 minutes before stocking to kill parasites and pathogenic bacteria.

5. Feed feeding: fresh small miscellaneous fish and snail meat are used as animal feed, and soybean meal, cooked corn and wheat are used as plant feed. After the parent shrimps are put into the box, they are cultured intensively, and the daily feeding amount accounts for 5-8% of the parent shrimps' weight, of which animal feed accounts for 40-50% and plant feed accounts for 50-60%, so as to ensure the nutrition required by the gonad development of the parent shrimps. The feeding frequency should be flexibly controlled according to the weather conditions, and it should be fed twice a day in sunny days and 1 time in rainy days or not. Usually, when the water temperature is about 20℃, feed it 1 time a day, and when the water temperature is about 28℃, feed it twice a day. The feeding amount in the morning accounts for 30% of the total feeding amount in the whole day, and the feeding amount in the afternoon accounts for 70% of the total feeding amount in the whole day.

6. Daily management: Clean the feeding residue left in the box 1 time every 3-5 days, and check whether the cage is damaged. If it is damaged, repair it immediately. Rinse the box with water pump from 9: 00 every night to 5: 00 the next morning to promote the full exchange of water inside and outside the box, and play the role of increasing oxygen and stimulating embryo development. After the parent shrimps are basically discharged, the parent shrimps are fished out in time, the cage is dismantled, and the shrimp seedlings are transferred to the pond for juvenile shrimp cultivation.

Artificial propagation technology of crayfish in cement pond

1. Preparation of aquaculture pond: Build several small ponds, each with an area of about 4 square meters and a depth of 70 cm. Before stocking parent shrimp, each square meter of culture pond should be thoroughly disinfected with about 200 grams of quicklime, and the newly-built cement pond should be disinfected after alkali removal.

The water depth of the cement pool is generally maintained at 50-60 cm. Artificial nests are made of asbestos tiles and red bricks at the bottom of the pool. The cement pool is covered with shading cloth. Water hyacinths are kept in the pool, covering two-thirds of the water surface. Configure the corresponding oxygen-increasing facilities.

2. Selection of parent shrimps: parent shrimps are generally selected in June-August, and the parent shrimps are required to be above 40g/ tail, with healthy physique, complete appendages, bright colors and no diseases or injuries on the body surface.

3. Release the parent shrimps: For the parent shrimps transported for a long distance, soak them in the pool water for 3-5 minutes before releasing them, then put them by the pool for 2-3 minutes, and repeat this for 2-3 times, so that the parent shrimps can absorb enough water, and then slowly put them into the pool around the pond. There are 40 parent shrimps per square meter, and the male-female ratio is 1: 1. At the same time, the specifications of the parent shrimps should be the same.

4. Parent shrimp cultivation: Before parent shrimp cultivation, intensive cultivation is needed to supplement shrimp nutrition and promote gonadal development. Generally, animals (such as minced fish, fish offal and animal scraps) and plant feed (such as soybean meal and bran) with high protein content are fed, and the ratio of animal feed to plant feed is 1: 1 or 3:2. Generally, it is fed 1 time at about 5 pm every day, and the feeding rate is 3-5%.

5. Water quality management: the water in the culture pond is changed every 3-5 days 1 time. If the water quality of the shrimp pond is poor, it is necessary to drain the pond water and clean the shrimp pond. When there is no oxygen in the water, start the aerator in time to aerate.

6. Fertilization and incubation: After intensive cultivation, the parent shrimps mate when the water temperature reaches 18℃ in September, and spawn in succession at the middle of 10. When the water temperature is 18-20℃, the incubation period of fertilized eggs is 30-40 days, and when the water temperature is 25℃, it only takes 15-20 days. When a large number of young shrimps appear in the culture pond, they should be collected in time.

7. Shrimp seedling cultivation: the harvested shrimp seedlings are transported to the shrimp seedling cultivation pond in time. The cement pond with an area of 20-40m2 and a water depth of 1m is the best for shrimp fry cultivation pond, and the soil pond with an area of 1-3mu, a slope ratio of 1:2 and a water depth of 0.5- 1m can also be selected. Apply 500 kilograms of decomposed human and animal manure per mu to cultivate natural feed. A certain number of aquatic plants (water peanuts, water hyacinths, etc.). ) put it in the pond for young shrimps to inhabit, molt and hide.

Choose sunny morning or cloudy day to release young shrimps, with 150-230 per square meter. Feed soybean milk 3-4 times a day in the first week after stocking; In the second week, animal feeds such as small fish, shrimp, snail meat, earthworm, silkworm chrysalis, etc. were mainly fed, and mixed with corn, wheat and fresh plant stems and leaves to make paste feed, which was fed/kloc-0 times in the morning and evening, and 70% of the whole day's amount was fed in the evening. In the early stage, the daily feeding amount was 250-400g per 10,000 young shrimps, and then it was about 10% of the shrimp weight in the pond. During the cultivation process, change the water every 7- 10 days/time, and change the water every time 1/3; Every 15 days or so, each cubic meter of water is mixed with 20 grams of quicklime to make slurry, and the whole pool is evenly sprinkled 1 time.

After 25-30 days of cultivation and 5-8 times of molting growth, the body length of young shrimp can reach 3 cm. In April next year, shrimp seedlings can be transferred to soil ponds for conventional culture.

Key points of crayfish culture and fishing in high temperature season

Water quality adjustment In hot season, the water temperature is high and the water quality changes rapidly, so it is necessary to observe it frequently and adjust it in time. The specific method is: (1) change water 1 time every 3-5 days to replenish fresh water, and change water15-20 cm each time; (2) Aquatic plants are easy to die in high temperature season, so the dead aquatic plants should be fished out in time to keep the breeding environment clean; (3) Spraying microbial inoculum regularly for 0 times every 10 ~ 15 days can effectively improve the water quality; (4) The transparency of the pool water should be controlled above 40cm.

When the feed is fed in high temperature season, freshwater crayfish have the habit of digging holes to escape the heat, and the activity during the day is relatively reduced. To control the daily feeding amount, it is advisable to feed a little feed residue 2 hours after feeding. Feeding time is mainly in the evening, and it is not necessary to feed in the morning.

The water temperature of aquatic plants is high in the high temperature season. Freshwater crayfish eat less and go into caves to escape the heat, which affects the growth and fishing of freshwater crayfish. Therefore, it is necessary to maintain the aquatic plants in the aquaculture pond to reduce the water temperature. The area of aquatic plants in the pond should account for 1/2 ~ 2/3 of the total water surface. If there are few aquatic plants in the pond, a large number of water peanuts can be transplanted around the breeding pond. Water peanuts should be thoroughly cleaned and disinfected with 20 mg/L potassium permanganate solution to remove fish eggs and germs.

Catching freshwater crayfish in time is usually carried out in cages. After the cage is lowered, the freshwater crayfish should be properly stimulated by using the habit of upstream crawling, so as to increase the activity of freshwater crayfish, promote its range of activities and increase its catch. Taking advantage of the gluttony habit of freshwater crayfish, stop eating 1 ~ 2 days before fishing, and add high-quality bait with strong fishy smell or obvious fragrance when fishing to lure freshwater crayfish into cages, which can improve the fishing effect. In a pond where the fishing effect is not obvious, first check the shrimp quantity in the pond. If the amount of shrimp is large, we can fish by raising and lowering the water level. The method is as follows: firstly, reduce the water depth of the pool by 1/2, arrange the ground cages and appropriately increase the number of ground cages, and then slowly add water to the pool. Lowering the water level will stimulate freshwater crayfish. Once fresh water is added, the activity will increase, the desire to escape will be enhanced, the range of activities will be enlarged, the probability of entering the cage will be greatly improved, and the fishing efficiency will be significantly improved.

Water quality management technology of crayfish culture pond

Freshwater crayfish have strong adaptability to the environment and hypoxia tolerance, and can even directly use oxygen in the air. However, long-term exposure to anoxia, excessive water quality or deteriorating environment will affect the molting speed of freshwater crayfish, thus affecting its growth. Therefore, water quality is an important factor limiting the growth of freshwater crayfish and affecting the shrimp culture yield. Poor water quality will also promote the reproduction of parasites, bacteria and other harmful organisms, leading to the occurrence and spread of diseases. When the water quality is seriously poor, crayfish will die. When freshwater crayfish are cultured in high density in ponds, the transparency of pond water should be controlled at about 40 cm, and it should be adjusted in time according to seasonal changes and water temperature and quality conditions, and water should be added, changed and fertilized in time to create a good water environment. The water quality management of freshwater crayfish culture should master the following principles:

The principle of "shallow spring and full summer". In spring, the water level is generally kept between 0.6 ~ 1 m, and shallow water is beneficial to the growth of aquatic plants, snail reproduction and young shrimp molting. When the water temperature is high in summer, the water depth should be controlled at 1 ~ 1.5m, which is beneficial for crayfish to survive the hot season.

The principle of "gain weight first and then lose weight". Keeping the aquaculture water body "fat, lively, tender and cool", the early shrimp seedlings and fat water can cultivate plankton, which is conducive to improving the survival rate of shrimp seedlings; The water quality is thin in the middle and late stage, which can promote the rapid growth of crayfish and increase the yield. Generally, the transparency of water in the early stage is about 30 cm, and the transparency in the later stage remains above 40 cm.

Improve aquaculture water quality. Spraying 1 time of quicklime water every half month, using 10 kg of quicklime per mu of water surface, with a depth of 1 m, can keep the pH value of the pond water between 7.5 and 8.5, which can increase the concentration of calcium ions in the water body and promote the molting growth of freshwater crayfish. Regularly apply microbial agents to improve the water quality and bottom quality of aquaculture ponds.

Prevention and treatment of various diseases of crayfish

The treatment of shrimp diseases should be based on the principle of "prevention first, combining prevention with control". Here are some prevention and treatment methods of common diseases of crayfish.

First, gill rot

The pathogen of gill rot is bacteria, and the symptoms are black gill filaments and local mildew of diseased shrimp.

Prevention and control methods: remove the residual bait and dirt in the shrimp pond frequently, inject fresh water, and keep the dissolved oxygen in the water above 4 mg/L to avoid water pollution. Spraying 2 g/m3 bleaching powder in the whole pool can have a good therapeutic effect.

Second, black gill disease

Black gill disease is mainly caused by serious water pollution and mold infection of shrimp gill silk. The symptom is that the gills change from red to brown or light brown until they turn black completely and the gills atrophy. Sick shrimps often lie motionless on the shore and eventually die of breathing difficulties.

Prevention and control methods: keep the water clean with sufficient dissolved oxygen, and adjust the water quality with quicklime regularly. The diseased shrimps are soaked in 3% ~ 5% salt solution for 2 ~ 3 times, each time for 3 ~ 5 minutes, or sprayed in the whole pool with methylene blue 10g/m3 dissolved water.

Third, rotten tail disease.

Tail rot is caused by crayfish and shrimp being injured, swallowing each other or being infected by chitin decomposing bacteria. At the initial stage of infection, there are blisters on the tail of the diseased shrimp, and the edges are ulcerated, necrotic or incomplete. With the deterioration of the disease, the ulcer develops from the edge to the middle. When it is seriously infected, the whole tail of the sick shrimp will fester and fall off.

Prevention and control methods: when transporting and releasing shrimp seedlings and shrimp seeds, do not pile up and damage shrimp bodies. During the feeding period, feed should be fully and evenly fed to prevent shrimps from competing for food or killing each other because of insufficient feed. In case of this disease, use tea residue 15 ~ 20g/m3 immersion liquid to splash it all over the pool; Or sprinkle with 5 ~ 6 kg/mu of quicklime in the whole pool.

Four. Polyconchocerciasis

The pathogen of polycephalosis is polycephalosis, and the symptom is that it is difficult for shrimp to shell smoothly. During the shelling process, sick shrimp often dies, and both larvae and adults can occur, which is harmful to young shrimp.

Prevention and control methods: thoroughly clean the pond and kill the pathogens in the pond. When this disease occurs, you can often change a lot of water to reduce the number of coagulated worms in the pool water.

V. Ciliary disease

Ciliate disease is a common disease, such as tired branches and bollworms. Ciliates attach to the body surface, appendages and gills of adult and young shrimp, which will hinder the breathing, activity, feeding and shelling of shrimp and affect its growth. Especially when a large number of gills are attached, it will affect the gas exchange of gill filaments and lead to the death of shrimp due to suffocation and hypoxia.

Prevention and control methods: keep reasonable stocking density, pay attention to the environmental sanitation of shrimp ponds, and change fresh water frequently to keep the water fresh. The diseased shrimps are soaked in 3% ~ 5% salt solution for 3 ~ 5 days as a course of treatment, or soaked in 25 ~ 30 mg/L formalin solution for 4 ~ 6 hours for 2 ~ 3 times continuously.

Key points of overwintering management of Procambarus clarkii

In order to improve the overwintering survival rate of Procambarus clarkii and lay a good foundation for the breeding production next year, the overwintering management of Procambarus clarkii should be done well in winter to ensure the safe overwintering of Procambarus clarkii. 1. Deepen the water level in the pond. In winter, cold air is frequent, and the water temperature in the pond drops obviously. In order to ensure the safety of young shrimps who have not entered the hole for the winter, the water level should be raised in time to keep the water level above 60 cm, so as to maintain the stability of the bottom water temperature. Avoid the drastic change of water level and affect the excavation of Procambarus clarkii. 2. Strengthen the management of aquatic plants. On the one hand, the mask of aquatic plants in the pond can stabilize the water temperature in the pond, and on the other hand, it can provide shelter for the young shrimp that have not entered the hole at the bottom of the pond to avoid enemy damage. If there is nothing hidden at the bottom of the pond, young shrimps will be easily swallowed by benthic wild fish such as crucian carp and carp, which will affect the yield of Procambarus clarkii next spring. The species of aquatic plants that can survive the winter is oriental grass. Aquatic plants salvaged from the river should be cleaned or exposed to the sun for 2 hours before being put into the pond to avoid bringing fish eggs and eggs attached to aquatic plants into the pond. Aquatic plants should be distributed along the coast, accounting for about 50% of the total water surface, forming an aquatic plant belt (block), which is fixed with bamboo poles to prevent it from being blown by the wind. In the absence of aquatic plants, straw can be thrown into the pond and sank to the bottom of the pond for young shrimp to inhabit and climb. 3. Timely and appropriate feeding When the weather gets warmer and the water temperature rises, and the activity of Procambarus clarkii is observed near the pool, you can choose to feed it at noon on a sunny day, and feed it to the young shrimp with crumb feed such as rice bran and barley, supplemented by chopped fresh wild fish and shrimp to strengthen nutrition. 4. Do a good job in pond restoration and reinforcement of escape prevention facilities. Through the drilling of Procambarus clarkii, the pond restoration and the reinforcement of escape prevention facilities in winter leisure period should be done well. Strengthen anti-escape facilities such as asbestos tiles and nets, repair the collapse and leakage of ponds caused by crayfish excavation, and prepare for next year's production.