Feeding method of crayfish 1. Choose a pond
The water source requires fresh water quality, sufficient dissolved oxygen and no pollution. It is best to use loam. The shore is more than 3m wide, with a slope of 1: 2.5, a water depth of 0.8 ~1.5m and a pH value of 7.5 ~ 8.5. The pond area should not be too large, generally 3 ~ 8 mu, rectangular, east-west direction. When fresh water is injected into the pond, it should be filtered with 20~40 mesh gauze to prevent wild fish and fish eggs from entering the pond with the water flow. According to the pattern of high irrigation and low drainage, drainage channels are built to ensure that irrigation can enter and exit. Crayfish have strong escape ability and need to build escape prevention facilities. Usually, plastic film, mesh, calcium-plastic board or cement board are used to set up escape prevention facilities around the pond ridge to avoid the entry of pests and the escape of crayfish.
Second, clean the pond and disinfect it
Cleaning and disinfection of ponds can effectively kill harmful organisms (catfish, loach, snakehead, snake, mouse, etc. ), wild miscellaneous fish (carp, crucian carp, etc. ) and pathogens in the pond. You can use quicklime and bleaching powder, which is economical and safe. The specific operation method is: 1. Sterilize with quicklime. Dry disinfection: 70kg of quicklime is used per mu, and water is splashed all over the pool. If possible, I will hold it with a rake. After hanging in the pond for a week, fresh water will be injected. Disinfection with water: each mu of water surface is calculated according to the water depth 1m, and after being dissolved in water with quicklime 130kg, it is evenly sprinkled all over the pool. 2. Disinfection of bleaching powder. After the bleaching powder containing 30% available chlorine is completely dissolved, it is sprayed evenly in the whole pool, and the dosage is 25 kg per mu.
Third, plant aquatic plants.
? Is the lobster delicious? Is there any grass in the pool? Lobster is not big, but the grass in the pond is in charge. ? Aquatic plants play an important role in lobster culture. The first kind of aquatic plants can fill the deficiency of lobster bait and supplement a lot of vitamins. Secondly, it can prevent wind and waves, absorb some harmful substances in water, purify water quality and balance water environment; Third, it can provide hidden and roosting places for young shrimp and shrimp shells, and reduce bullying by the strong. Generally, the planting area of aquatic plants accounts for half of the whole pond area. The varieties available are: dwarf reed, Zizania latifolia, Elodea nuttallii, black algae, etc. If possible, you can also put some empty cans, bamboo tubes, tree roots and other wastes at the bottom of the water body, which are the favorite habitats of crayfish.
Fourthly, fertilization in shrimp ponds.
What are the feeding methods of crayfish? Some people think it doesn't matter whether the lobster pond is fertilized or not. In fact, when lobsters are released to cultivate food organisms, applying a proper amount of organic fertilizer in the shrimp pond can directly provide natural bait for the shrimp after entering the pond. Choose 400 kg/mu fermented organic fertilizer to maintain the corresponding fertility of the pool water. In the process of feeding, with the gradual deepening of the water level, it is necessary to topdressing the decomposed organic fertilizer. The choice of quantity and time depends on the fat and thinness of the water, generally not exceeding 80 kg at a time. The transparency of the pool water is kept at about 35 cm.
Five, lobster socks
The release of lobster fry is divided into spring release and autumn release. Requirements of neat specifications, complete appendages, no disease, no injury, no foot. Wash with 5% saline water bath for 5~ 10 minutes before stocking to kill parasites and pathogenic bacteria. The purchased shrimps should be soaked in the pool water 1 minute when entering Tangqian, lifted and put on hold for 2-3 minutes, and then soaked 1 minute. Repeat this for 2-3 times to make the larvae release after absorbing enough water on the body surface and gill cavity, which can improve the survival rate. From the experience of farmers for many years, the survival rate of shrimp seedlings is very low when they are transported abroad for a long distance. Proper mixed culture of silver carp and bighead carp in ponds can improve water quality and make full use of bait resources. 1. Put shrimp in spring. In mid-March, 5000~6000 young shrimps with a body length of 3 ~ 5 cm were released. 2. Put parent shrimps in autumn. Around September, 500 artificially selected lobster parent shrimps were put into each mu, and the male-female ratio was 3∶ 1.
Sixth, feed selection
Lobster is omnivorous, and animal feed, plant feed and various artificial feeds should be used together at different stages. Animal feed mainly includes small fish pieces, dried fish meal, snail meat and various animal offal; Plant feed mainly includes rapeseed cake, soybean meal, bran, wheat, corn, pumpkin, various vegetables and aquatic plants.
Seven, feeding management
Crawfish have been dormant for many days, and it is their habit to come out at night and move for food at night. Feed should be fed every morning 10 and 4 pm, and the amount of feed in the afternoon accounts for about 70% of the whole day.
The suitable water temperature for the rapid growth of crayfish is 22~32℃. The feeding amount of 6- 10 crayfish is gradually increasing, and the daily feeding amount can be appropriately adjusted according to the actual fishing situation, and can be appropriately increased or decreased according to the weather, water quality and shrimp foraging situation. As the saying goes, Tsing Yi undresses and wears a red coat, and the variety of feed is good. Throw less in rainy days and when the water is thick, and feed all the shrimps in sunny days.
Eight, daily management
Crawfish farming should also patrol the pond every day, paying attention to the change of water color and lobster activities. If shrimps are found ashore or crawling on aquatic plants to drive them away, check whether the water body is short of oxygen or the water quality is getting worse, and take corresponding measures, such as increasing oxygen and changing water. The pH value should be kept at about 7.5, and the transparency should be about 35 cm. Change the water every half month in April, May and June, every ten days in July, August and September, and change the water every time 1/3. Water the quicklime once every twenty days, and use quicklime 10 kg/mu each time. From spring to midsummer, the water level rises gradually, with the deepest not exceeding 1.5m ... to maintain the normal growth of aquatic plants and a certain coverage area. When lobsters molt intensively, try to keep the surrounding environment quiet. After molting, increase the feeding of animal palatable feed and reduce mutual killing. Lobster diseases are much less than other aquatic products, but they should not be underestimated. Prevention is the most important thing in daily life. It is the nature of lobster to like to escape, especially in flood season, so it is necessary to strengthen inspection to prevent shrimp from escaping.
Nine, lobster fishing
Lobster fishing tools are mainly ground cages. The specific operation method is to set a ground cage near the aquatic plants in the pond, tie both ends of the ground cage tightly, and collect lobsters that meet the commercial specifications from the ground cage the next day. In addition, lobsters can be caught by hand after copying the net or draining the pool water. Lobster fishing can take the way of catching big and keeping small, which is conducive to increasing production. Fishing begins in May and ends at the end of September.
Culture method of crayfish. cultural facilities
Suitable pond area is 4 ~ 10 mu, depth is 1 ~ 1.5m, and slope ratio is 1: 2.5. The bottom of the pond is flat, loam is the best substrate, the slope soil of the pond is hard, the water retention of the pond is good, and the water level is easy to control. Rich in water and pollution-free. According to the pattern of high irrigation and low drainage, drainage channels are built to ensure that irrigation can enter and exit. Crayfish have a strong ability to escape, so it is necessary to build anti-escape facilities. Usually, the pond ridge is surrounded by plastic film or calcium-plastic board and supported by bamboo piles or wooden stakes to prevent escape.
Second, the preparation before stocking
1. Clean and disinfect the pond thoroughly. 20 ~ 30 days before the shrimp seedlings are released, drain the pond water, remove excess silt, repair the pond ridge, and thoroughly clean and disinfect the pond with 75 kilograms of quicklime or bleaching powder, bleaching powder essence and other drugs per mu.
2. Apply enough base fertilizer and 500-600 kilograms of decomposed livestock manure per mu to cultivate rotifers, cladocera and copepods plankton, and provide delicious bait for shrimp seedlings and species.
3. Aquatic plants such as black algae, POTAMOGETON malayi and Elodea malayi are planted in the aquatic plant pond, accounting for 2/3 of the shrimp pond area. At the same time, set up a net, or set up bamboo tubes, plastic pipes, etc. To provide a place for crayfish to inhabit, molt and hide.
Third, raise shrimp seedlings and shrimp species.
1. Various breeding modes can be adopted. (1) Summer stocking mode. The first batch of young shrimps hatched in that year were mainly stocked, and the stocking time was in the middle and late July, and the size of young shrimps was above 0.8 cm. Stocking 30,000 to 40,000 tails per mu. (2) Autumn stocking mode. The large-scale shrimp fry or shrimp species cultured in that year are mainly stocked, and the stocking time is from mid-August to September. If the size of shrimp seedlings is about 1.2cm, 25,000 ~ 30,000 shrimps will be stocked per mu; Shrimp species with a size of 2.5 ~ 3 cm are stocked1.50,000 ~ 20,000 per mu. A few can meet the market specifications by the end of the year, and most of them will be caught and listed in June-July of the following year. Commercial shrimp weighs only 25 grams and yields 300-500 kilograms per mu. (3) Winter and spring stocking mode. Generally, the goods are stocked in February or March-April of the following year after 65438+. The shrimp that did not meet the market specifications in that year were mainly stocked, with specifications of 0/00 ~ 200 per kilogram and 0/5000 ~ 20000 per acre. After breeding in winter and spring, it will be listed in June and July. Commercial shrimp can weigh up to 30 grams and yield 400-500 kilograms per mu.
2. Seed quality The requirements for shrimp seedling quality are: (1) the specifications are neat. The size of young shrimp is more than 0.8 cm, and the size of shrimp species is about 3 cm. The specifications and varieties of shrimps stocked in the same pond should be consistent, and all of them should be stocked at one time. (2) strong physique, complete appendages, no disease or injury, and strong vitality. (3) artificially cultivating shrimp seedlings and shrimp species. If it is a wild shrimp species, it should be domesticated for a period of time before stocking, so as to avoid fighting and killing each other.
3. Precautions: (1) Stocking should be carried out in sunny mornings in winter, and in sunny mornings or rainy days in summer and autumn to avoid sun exposure. (2) Wash shrimp 10 minute with 3% ~ 5% saline water before stocking to kill parasites and pathogenic bacteria. (3) Shrimp species purchased from other places should be treated slightly before stocking because they have not been watered for a long time. Soak shrimp seeds in the pool water for 1 min, lift them for 2-3 minutes, then soak them for 1 min, and repeat this for 2-3 times, so that the surface and gill cavity of shrimp seeds can absorb enough water before stocking, and the survival rate can be improved. (4) In the pond where crayfish are cultured, some silver carp and bighead carp are mixed appropriately to improve the water quality and make full use of the bait resources.
Fourth, scientific feeding.
Crawfish are omnivorous and gluttonous. Feed feeding, grasp the following three points.
1, according to the nutritional requirements of crayfish at the same growth stage, do a good job of feed combination and feeding. In the larval and larval stages, crayfish feed on rotifers, cladocera, copepods and aquatic insects larvae, while in the adult stage, they eat both animal feed and plant feed. After releasing shrimp seedlings and shrimp seeds, timely fertilization should be carried out to improve water quality. During the rapid growth period of 8- 10 crayfish, bran, bean cake and green feed should be fed, and animal feed should be fed appropriately. During11~ 65438+February, crayfish were mainly fed with animal feed.
2. Feed crayfish according to their living habits and feeding characteristics. Crayfish Crayfish mostly hunt for food at night and have the habit of competing for food and gluttony. Feed is fed once a day in the morning and afternoon, mainly once in the afternoon, accounting for 70% of the whole day's feed; Adopt the method of feeding at fixed quality, fixed quantity and fixed time, and feed them sufficiently and evenly to ensure that every shrimp is full and avoid competing for food.
3. Feed prawns reasonably according to the weather, water quality changes and the feeding situation of prawn activities. The suitable water temperature for crayfish growth is 20 ~ 32℃. From August to1October, the feeding amount of crayfish is relatively large, and the daily feeding amount can be arranged according to 6% ~ 10% of the shrimp weight in the pond, and the whole dry material or batch is 2% ~ 4%, which can be appropriately increased or decreased according to the weather, water quality and shrimp foraging situation. Continuous rainy weather or water quality is too strong, you can feed less, and feed more when the weather is good; Feed less shrimp when molting, and feed more after molting; Shrimp should be fed less during the onset season and more during normal growth. Let shrimp eat well, reduce waste and improve feed utilization.
Verb (abbreviation for verb) daily management
1. Establish patrol pool inspection system. Patrol the swimming pool every day, and take countermeasures in time if any abnormality is found.
2. Control water quality. Keep the dissolved oxygen in the shrimp pond above 5g/L, the pH value is 7 ~ 8.5, and the transparency is about 40cm. /kloc-change the water every 0/5 ~ 20 days,13. Sprinkle quicklime water every 20 days, and use quicklime 10 kg per mu. Keep the water level stable and don't go up and down.
3. Strengthen the management of habitat molting sites. There are always many aquatic plants in the shrimp pond. It is forbidden to disturb a large number of shrimps when molting, and feed high-quality palatable feed immediately after molting to prevent cannibalism and promote growth.
4. Prevent escape and disease. Strengthen inspections in flood season to prevent shrimps from escaping. Do a good job in disease prevention and enemy elimination.
Six, commercial shrimp fishing and transportation
1, fishing. Fishing can be concentrated in June-July and11~ 65438+February. Use tools such as cage net and hand-copied net to capture first, and then capture in the dry pool. You can also catch the big ones and let the small ones go. There are fish all year round.
2. transportation. Commercial shrimps are usually transported in styrofoam boxes, plastic bags or refrigerated trucks. Keep the shrimp moist during transportation, do not squeeze, and improve the survival rate of transportation.
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