Management techniques of cultivating Loach in Pond in Winter

The technology of raising Loach in pond in winter is known as "ginseng in water". It has delicious taste, delicate meat and rich nutrition. It also has high value in medicine, and it is one of the important aquatic products exported by our country. Misgurnus anguillicaudatus has become an important aquaculture species because of its strong adaptability, few diseases, high survival rate, strong fecundity, convenient transportation and easy availability of bait.

Seedling cultivation

1. Pond conditions: the soil pond is the best for seedling cultivation, with an area of 30-100 square meters and a depth of 40-60 cm. Fish slips are excavated in the pond to facilitate its habitat and summer protection against cold. The bottom of the pond is compacted, fish nets are set up at the inlet and outlet of the pond, the bottom of the pond is laid with 15-20 cm silt layer, duckweed is placed in the pond, and the covering area is about 1 / 4 of the total area.

2. Clear the pond and cultivate water: 10 days before the loach seedlings go into the pond, clean the pond with 20-30 kg of quicklime and clean the pond with water. After disinfection, 300-400 kg of mature human and animal manure were applied per mu as basic fertilizer to cultivate water, and the pool water was added to 30 cm. After the water color turns green and the transparency is 15-20 cm, Loach seedlings can be released.

3. Seedling restocking: Loach seedlings will open their mouth to eat on the second day after emergence of the membrane. After 3-5 days of feeding, the body length is about 7 mm, the yolk sac disappears, exogenous nutrition, and can swim freely. At this time, the loach seedlings can enter the seedling cultivation stage. The stocking density of Loach seedlings should be 8-1000 per mu, and those with micro-flow conditions can be increased appropriately. Note that the same batch of Loach seedlings with the same hatching specifications should be released in the same pond to ensure the balanced growth of the seedlings and improve the survival rate.

4. Feeding and management: Loach seedlings just down the pond have a strong selectivity to feed, so it is necessary to cultivate palatable baits such as rotifers and small phytoplankton, which are filtered by a 50-mesh standard sieve and fed along the edge of the pool. and properly feed cooked egg yolk, fish meal, milk powder, bean cake and other refined feed. When the length of the Misgurnus anguillicaudatus seedling reaches 1 cm, it can eat insects, insect larvae and organic debris in the water, and can be fed with boiled bran, bran, corn flour, wheat flour and other animal feed, such as chopped fish, shrimp, snail mussel meat, 3-4 times a day. At the same time, gradually increase the proportion of formula feed in the feed to make it gradually adapt to artificial formula feed. Feed should be put on the table about 5 centimeters away from the bottom of the pool. The daily feeding amount at the initial stage is 2% of the total body weight of Loach seedlings, 5% of the total weight, and 8% of the total body weight of Loach seedlings at the later stage. Loach likes fertilizer and water, so it should be applied in time, such as chicken and duck manure, soaked in water with woven bag, chemical fertilizer, ammonium nitrate when the water temperature is low, and urea when the water temperature is high. At ordinary times, we should do a good job in water quality management, timely injection of new water, and adjust the water quality. When raised for more than 1 month, Loach seedlings are 3-4 cm long and can be transferred to adult Loach culture when they begin to drill mud.

Adult Loach culture

1. Pond construction: choose a place with shelter from the wind to the sun, convenient water diversion, weak alkaline substrate and no pesticide pollution to build a pond, which can be a cement pond or a soil pond. The wall of the earth pool needs to be built with bricks and stones, or hammered with concrete, and the bottom of the pool needs to be rammed so that it is sturdy and durable without loopholes, and the bottom is covered with 20-30 cm of fat mud. The inlet and outlet is blocked with a wire or plastic net, and the bottom of the pool is tilted toward the outlet for drainage and fishing.

2. Water cultivation and sowing: the pond is cleaned and disinfected according to the seedling cultivation method, the water depth is kept at 30-50 cm, and organic fertilizers such as pig manure are applied to cultivate water quality, with a dosage of 100 square meters and 20-30 kg. After the medicine disappears and the pond water turns into fertilizer, the species of Loach can be put in, and those with running water can be increased appropriately.

3. Feeding and management: on the basis of improving water quality and providing natural bait, it is necessary to increase the feeding of animal feed such as maggots, earthworms, clam meat, fish meal, small fish meat, livestock and poultry scraps, as well as plant feed such as wheat bran, rice bran, bean dregs, cakes, or artificial compound feed. It is generally fed once a day in the morning and afternoon, and the daily feeding amount is 5% of the body weight of Loach. 10%. Feeding should be flexibly controlled according to water quality, weather and food intake. The appetite of Misgurnus anguillicaudatus gradually increases when the water temperature is above 15 ℃. The range of 20-30 ℃ is the optimum temperature for feeding. The appetite of 25-27 ℃ is especially strong. It can not be fed in thunderstorm days when the temperature is more than 30 ℃ or below 15 ℃. In addition, reasonable fertilization should be carried out according to the water quality and fertility, the transparency of the pool water should be controlled at 15-20 cm, and the water color should be yellowish green. When the water temperature reaches 30 ℃, the pool water should be changed frequently and the water depth should be increased; when the Loach often swims to the surface to "swallow air", it indicates that there is a lack of oxygen in the water, so fertilizer should be stopped and new water should be injected. The depth of the pond water should be increased in winter, and barnyard manure such as cow manure and pig manure can be applied in the pond corner to improve the water temperature and ensure the Loach to survive the winter safely.

Fishing and transportation

The fishing of Loach is usually carried out by means of flushing, trapping, dry pond and so on.

1. Flushing method: put the fishing tools at the inlet, and then put the water into the pond. Misgurnus anguillicaudatus is stimulated by running water, upstream against the current and clustered near the inlet. At this time, the pre-set gear will be pulled up, and the Loach can be captured.

2. Trapping method: put boiled cattle, sheep bones or fried rice bran and wheat bran in nets or fish cages and attract Loach with their fragrance.

3. Dry pond method: in winter, when the water temperature drops to 15 ℃-12 ℃, the Loach will drill into the sediment of the pond and can only be caught in the dry pond. First drain the water, divide the pond and rice field into several pieces, dig the drainage ditch in the middle, and the Loach will be concentrated in the drainage ditch for easy capture.

Loach is mostly fresh sales, such as improper transportation is easy to lead to death, resulting in losses. Can be transported by bamboo basket, each bamboo basket containing Loach 25 kg, the bottom of the bamboo basket covered with plastic film, add water 2-2.5 kg, and then put into the live Loach; during transportation, add water every 1.5 hours to ensure that the Loach is fresh.

Disease prevention and cure

In the process of Misgurnus anguillicaudatus culture, attention should be paid to the prevention and control of diseases, such as red fin disease, water mildew disease, air bubble disease, curved bone disease, rotifer disease, tongue cup disease, pesticide poisoning and other biological pests. The main prevention and control methods are as follows:

1. Rotten fin disease: the symptoms include congestion and ulceration around the fins, abdominal skin and anus of the Loach, whitening and festering of the caudal and pectoral fins, edema and erythema on both sides of the fish from head to tail. The control method is to sprinkle with 1 gram of bleach per cubic meter or 0.1 grams of furazolidone in the whole pool.

2. Red fin disease: this disease is harmful to Misgurnus anguillicaudatus and has a high incidence, which is caused by bacilli. The symptoms are as follows: first, the fin or part of the body surface is peeling off, showing gray color, the muscles begin to rot, the anus turns red, then blood spots appear in these areas, and gradually turn dark red, and in severe cases, the fins fall off and do not feed until death. It is mainly popular in summer. The method of prevention and treatment is to avoid fish injury, and 4% salt water bath should be used to disinfect the fry before stocking.

3. Water mildew: Loach eggs are treated with 400 grams of salt and 400 grams of baking soda per cubic meter of water for 1 hour. The method of prevention and control is to avoid mechanical damage as far as possible when catching and transporting Loach; wash the Loach with 4% salt water for 5-10 minutes.

4. Printing disease: the focus is generally oval-shaped, round-shaped, edema with erythema. The affected area is mainly at the base of the caudal stalk. It is popular from July to August. The treatment can be sprinkled with 1 g / m3 of bleach or 2Mel's 4 g / m3 of gallnut in the whole pool.

5. Rotifer: parasitic on Gill and body surface. Reduced food intake after illness, travel alone, serious cases of insects, if not timely treatment, will cause death, popular in May-August. The preventive measure is to clear the pond with quicklime and the treatment is to sprinkle 0.7 grams of crystal trichlorfon per cubic meter of pond water.

6. Tongue cup disease: parasitic on the skin or Gill of Misgurnus anguillicaudatus, usually ingesting food from the surrounding water as nutrition, it has little effect on Loach. However, if a large number of parasites on Loach seedlings, it will cause difficulty in breathing, and in serious cases, it will lead to the death of Loach seedlings. The disease can occur all the year round, especially from May to August. The prevention is that Loach species should be washed for 15-20 minutes with cupric sulfate solution of 8g / cubic water for 15-20 minutes before stocking. After the disease, the mixture of cupric sulfate and ferrous sulfate (5 ∶ 2) should be sprinkled all over the pond.

7. Parasitic diseases: the loach body is thin, often floating on the water surface, restless, or spinning on the water surface, and the body surface mucus increases. Most of them are caused by rotifers, tongue cups, and third-generation parasites. The control method is to sprinkle the whole pool with 0.7g copper sulfate and ferrous sulfate (5 ∶ 2) mixture per cubic meter to control rotifer and tongue cup disease.

8. White body red ring disease: the body of Loach is grayish white with red ring lines. The disease is caused by long-term preservation of Loach after capture. The way to prevent and cure the disease is to move the Loach into the static pool for a period of time.

9. Bubble disease: sick Loach fry float on the surface. It is caused by excessive oxygen or other gases in the water, which is mainly harmful to fish fry. The method of prevention and control is to sprinkle the whole pond with 4-6 kilograms of salt per mu; flush into the clear water or yellow mud water immediately; remove the decay in the pond in time and do not apply unfermented fertilizer. At the same time, master the amount of bait and fertilizer to prevent the deterioration of water quality.

10. Prevention and control of other enemies: in the pond where Loach is cultivated, the pond should be thoroughly cleared with quicklime. A tight net should be set up at the outlet to prevent harmful fish, aquatic insects, snakes and frogs from entering the pond to harm the seedlings or adults of Loach. If a water centipede is found in the pool, 90% of the crystal trichlorfon is sprinkled and killed in the whole pool at a concentration of 5 g / m3.