Blackfish artificial breeding technology
Black fish is a common food fish in China. It is also known as black mullet, fish, and snake fish. It is large and grows quickly. It is a benthic fish and usually inhabits in aquatic plants or muddy water or micro-flowing water. It is found in lakes, rivers, reservoirs, ponds and other waters. Black fish has less bone spurs, high meat content, rich nutrition, and nourishing care. This issue introduces a group of blackfish breeding techniques for farmers' reference. 1. Artificial propagation method In mid-May each year, it is the blackfish breeding season. Mature and robust black and white blackfish should be selected as broodstock in a ratio of 1:1. The female blackfish has enlarged and soft abdomen, black and white, with prominent ovary outlines, concave grooves in the center, protruding genital holes and pinkish color; male black fishes are purplish in color, and dorsal fins have transparent whites arranged from bottom to top. Small round spots, dark belly, slightly enlarged reproductive hole, dimpled, triangular, pale pink. Before spawning, the male and female fish are placed in cages for a day of rest. Do not feed the feed. This will facilitate spawning. The females were divided into two injections. The first needle was 1/3 of the full dose, 18 to 26 hours apart, and the remaining dose was injected once; the male dose was half of the female and was injected when the female gave a second needle. Most of the fish are injected into the thoracic cavity and injected 45 times with the fish. The depth of the needle is about 1 cm. Commonly used hormones include fleas and carp pituitaries. The dose is 4-8 females per kilogram, and the male is halved; or With chorionic gonadotropin, females range from 1.6 to 24,000 IU per kilogram, and males halve. One is to imitate the incubation of the natural environment. After injecting the oxytocide, the male and female are placed in the pool at a ratio of 1:1 and naturally spawn, fertilized and hatched. After the hatching of the fry, use the black fish's guardian habit to let it be free to care. This method saves labor and saves time. The disadvantage is that the survival rate of fry is low and the growth and development are inconsistent. The second is hatching in artificial cages. After injecting the oxytocide, male and female are placed in a cage of 4 to 6 square meters to lay eggs and fertilized at a 1:1 ratio, and then the broodstock is removed and put into the pond. The eggs were placed in a 40-mesh cage. Each box was fed with 10,000 fertilized eggs and hatched in microfluidic water. The environment at 22°C-27°C required 32-48 hours. The hatching rate depends on the fertilization rate and water quality. It should be frequent. Check for timely removal of unfertilized eggs. 2, breed stocking fish fry The black fish grows fast. In the early spring, the fry can develop commercial fish. The incidence of black fish is small, the survival rate is high, and the adult fish transportation is simple, and it is convenient for long-distance sales. Most of the black species come from natural sources, and can be caught by fishing nets, oysters, and kowloon bags, and most of the caught fish caught by hook fishing should not be used. Normally, fish stocks are purchased in the winter and stocking is gradually conducted. The stocking work should be completed before the end of April. If the stocks are not concentrated, they can be stocked one by one. Stocking from 5 to 150 g of black fish species from 8 to 16 tails per square meter is required. The black fish species in the box are of uniform specifications so as not to kill each other if there is not enough food. Whenever the seedling grows to a size of 3.5 centimeters long, it must be screened in time for stock raising, and as far as possible, the size of seedlings placed in each pot should be neat. Before fish ponds, they should be soaked with 3% to 5% of salt water for 10 to 15 minutes, and then put into the pool, and the fish should be 10 to 14 centimeters in length. The stocking density is 9,000 to 10,000 per mu; 20 cm species, stocking density of 8000 per mu. The use of hydrostatic cement tanks for the cultivation of first-year fingerlings shall be carried out once every 1 to 2 days. At the same time, the water shall be changed, the water exchange volume shall be 1/3, the summer flower volume shall be 200 to 300 per square meter, and the above-ground microfluidic cement tank shall be used. During cultivation, although there is no need for special water changes, the bottom sewage shall be discharged once every 7-10 days, 300-500 tails per square meter, 0.05-0.1 kg each at the end of each year, and half-ground or full underground cement tanks When it is not easy to discharge sewage, the siphon method can be used to remove the dirt every 5 to 7 days, while adding new water. 3, strengthen feeding management Blackfish is a carnivorous fish. The bait is mainly zooplankton and requires fresh and palatable. There are artificial compound feed, freshwater or small seafish, and leftovers after slaughter of livestock and poultry. The feeding is generally started from the beginning of April and fed once or twice a day. The daily feeding amount is 2% to 5% of the total fish weight in the box. Feeding should be done in accordance with the "four-determined" principle. Each pond should select 3 to 4 feeding points. The initial feeding amount is 10% of body weight, and it can be appropriately reduced to about 5% of body weight in the later period. Before the film is 2 centimeters old, it should be placed in cages of 10.50.5 meters in size made of 40 mesh cloth, with a density of 2000 tails per square meter. 4 to 5 days after the film is fed, rotifers or cladocerans, copepods, etc. are fed in small quantities for 4 to 4 hours for 3 to 4 days; afterwards, the number of feedings is increased, the number of feedings is reduced, and the transition to 1 gradually occurs. 2 times a day. When the black fry reaches 2 cm, it is exchanged for a cage made of 8-16 mesh of summer flower nets, with an area of ​​10-15 square meters, a rectangle being good, and a density of 500-600 tails per meter. At 4 to 5 centimeters, feed fish and mud to add zooplankton. In order to prevent dirt and filamentous algae from blocking the mesh, wash it once a day, replace it once a week, and thoroughly disinfect the cage. Intensive breeding methods, body length of 10 cm or more, after 8 to 9 months of culture, survival rate of 75% to 80%, an average body weight of 0.5 to 0.7 kg, per mu 4000 to 5000 kg. Black fish in the Wang Shiwang long season seasonings should be sufficient to ensure its fullness to promote rapid growth, and make appropriate adjustments based on fish eating conditions and weather changes. The bait is mainly oysters, fish gills and small fish, shrimp and so on. The daily feeding amount is 5% to 80% of the total weight of the fish body, and it is fed 2 to 3 times daily. When feeding, the sound of a beat is used as a signal, so that the seeds form conditioned reflexes and the floating colonies catch food. Observe the observation of blackfish feeding, activities, incidence trends and environmental changes. In the spring, change the pool water by 4/5, the high temperature season by 3 days for a small change, 7 days for a big change, enter the drainage pool to prevent escape, and the pool bowl is 50 cm above the water surface. The above is better. For the discharged sewage, necessary sewage treatment should be carried out. 4, scientific prevention of diseases Every morning and evening, we insist on two times of patrol ponds, observe the changes in feeding, activities, and water quality of the fish fry during the patrol pond, and find that the problem is solved in time. To prevent the occurrence of fish disease, we must regularly throw quicklime or bleaching liquid. Bleeding is caused by a variety of bacteria and viruses. There are vertical bleeding lines on the sides of the body wall of the pectoral fins and the body wall near the posterior edge of the lid. Hemorrhage symptoms occur, 3 to 4 days that there is a large number of violent death, 6 to September outbreaks. After the winter fishing, the pond must be thoroughly cleaned. Before the feeding of the bait, the fish must be disinfected with salt water. Formalin Quanchiposa should be used so that the concentration of the water in the pool can reach 20-30 ml/m3, or it can be splashed with the chlorine dioxide solution to make the pool water. Concentration of 0.5 grams per cubic meter is repeated four to six days later. Oral fish rehabilitation 2 or fish blood scattered, Yuxue Kangtai can, the amount used according to the instructions. Red bark disease is caused by Bacillus fluorescens, which causes local bleeding on the body surface and fish scales to fall off, especially on both sides of the abdomen. There are fins in the abdomen and fish movements are slow. Diseased fishes often float on the water surface and are weak and weak. Suddenly, it is secondary to water mould until it dies. Thoroughly clear the pond with quicklime so as not to harm the fish body. Disinfect with 0.5 mg/L or other chlorine-containing disinfectants per liter, such as trichloroisocyanuric acid, sodium dichloroisocyanurate, chlorine dioxide, etc.; oral fish suits Kang, Yu Xuekang, 250 grams of drug per 100 kilograms of fish to use or according to the instructions, mix feed and feed, and even served 3 to 5 days. Aquatic mildew is caused by water mold and occurs in all stages of blackfish growth. It is not easy to observe in the early stage of infection. When the water temperature rises to about 18°C, a large number of outbreaks occur. Blood spots appear on the fish surface, loss of appetite, weight loss of the fish, and melanin in the lesion area. Disappeared, appear gray, dull color, outliers alone. Finally, a white flocculent filament grows and the muscles become turbid white until death. Before the stocking, 100-150 kg of lime are used to dry clear ponds per acre. Adult fish ponds are regularly disinfected with quicklime or bleaching powder; 30 to 50 grams of potassium permanganate per cubic meter can be used during the onset of the disease. Seed fishing, transportation, operations and other processes should be careful to prevent fish injuries. Http://Content/472c7215-7592-4a58-8e02-26ed6144d45b?cType=2 Canned Green Peas,Green Peas Canned,Green Peas Tin,Canned Green Peas Canned ZHANGZHOU TAN CO. LTD. , https://www.zztancan.com