Breeding method of Xuyi crayfish

How to raise crayfish can be regarded as a hot item in the market, but many rumors say that crayfish like dirty water, so shrimp farmers have no choice but to raise it. So what are the feeding methods of crayfish?

First, 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.

"Lobster is good, there is no grass in the pool. The lobster is not big, and the grass in the pond is the owner. " 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.