The risk of grass carp culture is small. What are the skills of grass carp culture?

The risk of grass carp culture is small. What are the skills of grass carp culture? Grass carp grows fast, its meat is fat and delicious. Grass carp is a common herbivorous fish. Under the standard of human feeding, all kinds of aquatic plants, terrestrial Cyperaceae plants and various concentrated feeds are fed. Because of its rapid growth and wide sources of feed, it is one of the four major fish in China. If you want to raise grass carp well, you must know what the breeding technology of grass carp is like. Here, I will tell you five key points of grass carp culture technology.

Culture Technology, Natural Environment and Pond Selection of Grass Carp 1

Grass carp is the easiest to get sick, so there should be a professional farm to breed pollution-free grass carp, and there should be a certain scale of operation, and there should be no pollutants around the industrial base. Farms should have abundant water resources, excellent water bodies, unobstructed water inlet and outlet pipes, no communication between ponds, convenient transportation of fish, superior feed resources and excellent ecological environment protection standards.

2, fish species selection

If you want to raise grass carp well, you must use healthy and happy high-quality fish. Parents of self-propagating fish should come from qualified raw material farms confirmed by China. The fry culture is pollution-free, the quality conforms to the relevant specifications and has the characteristics of high quality. The standard is that self-reproduction and self-education are the best. If fish are introduced from other places, they must pass quarantine before they can be introduced.

3, fish disinfection and sterilization

Fish eggs need to be disinfected before they are put in. Chlorine dioxide 20-40ml/L per 5- 10-20mg/, edible salt 1%-3% per 5-20min, 8mg/L per 15-30min, potassium permanganate solution 15-. The ratio of free-range culture is 80∶20, that is, grass carp is 80% and fish culture is 20%.

4. Scientific and reasonable feeding

Grass carp feed on aquatic plants in natural rivers. In pollution-free culture in ponds, it is appropriate to choose granular feed which is scientifically and reasonably prepared with each other, so as to reduce the environmental pollution caused by residual bait and fully improve the utilization rate of bait. It should be tender, fresh and moderate with the fed flood and drought grass. Cake and XXX bait should be mildew-free, pollution-free and non-toxic, and be made into bait which is convenient for grass carp to eat, digest and absorb after crushing, soaking and boiling. The feeding standard of timely, accurate positioning and qualitative and quantitative analysis should be adhered to, and the temperature, water quality and fish food intake should be carefully observed to determine the effective feeding amount.

5. Feed fishery medicine effectively.

Fishery medicine is a chemical used to prevent and control aquatic animal and plant diseases. If the operation is improper, it is very easy to remain in the fish, which will lead to the deterioration of the quality of the fish, so it should be used with caution. Fishery drugs generally include pesticides, fungicides, insecticides and water bread improvers. At present, some traditional fishery drugs have been banned, such as chloramphenicol, furazolidone, sodium pentachlorophenol, malachite green, sulfathiazole and tylosin, which cannot be used in aquaculture. Pay attention to the use of fishery medicine.

Pay attention to 1 when feeding grass carp, and reduce the feeding of aquatic plants.

According to the experimental observation, grass carp can gain meat by eating 15kg of terrestrial aquatic plants 1 kg, and by eating 60 ~ 80 kg of aquatic plants 1kg. Therefore, in the case of abundant terrestrial aquatic plants, you can eat less or no aquatic organisms and aquatic plants.

2. Feed more tender forage.

The tender feed is rich in nutrition, less in methylcellulose and easy to digest and absorb. Feeding grass carp with tender feed can make grass carp grow faster and get sick less, and also reduce the feeding amount, feeding cost and economic benefits. Therefore, grass carp feed should be as tender as possible. The forage type should be long Julia tender grass with parallel veins, which is not suitable for feeding grass carp with poor appetite. It is best to feed the planted Sudan grass, Sudan grass and other green fodder and the collected wild plant long-leaved tender grass. Usually, we should observe the grass feeding situation of grass carp and feed more grass that grass carp likes to eat to meet the needs of grass carp growth and development.

3. Feeding methods should be appropriate.

Grass carp should be fed on time, in quantity and in a symmetrical way every day, so as to disperse the grass and make the fish eat well. It is necessary to adjust the feeding amount according to the actual conditions such as temperature, water body and thematic activities of fish species. It is forbidden to feed moldy forage stored for a long time to prevent grass carp from getting sick.

4. Feed different forage according to different fish species specifications and sizes.

Grass carp is small at the juvenile stage, so it is not allowed to feed coarse and hard forage. It is best to feed duckweed, Cyperaceae and other forage, or feed tender long-leaved grass after cutting. After that, with the increase of fish age and specifications, basic concentrate can be fed.

Free-range rearing of fish species should master four aspects: first, the fish species should be excellent, the fish species should be physically strong, the specifications and models should be neat, the scales and wings should be meticulous, and there should be no disease or injury. The fish in the box should be healthy physically and mentally, prevent trauma and avoid scraping the mucus off the fish with a net. Because the mucus of fish can bond and remove attached organisms and debris, it is a natural barrier for fish to resist pests and diseases. Therefore, when choosing fish, it is advisable to be smooth and sticky, and it is not good if it is not smooth. When catching fish, you should follow the direction in which the fish swims, and you can't catch it head-on to avoid injury.

Second, the specifications and models should be moderate. When you release fish, you should release large-sized fish of more than 20 cm, which has strong disease resistance, high survival rate and short feeding cycle and can be sold at the end of the year.

Third, the relative density is appropriate. Generally, the size of grass carp cultured in cages is between 300g/tail and 500g/tail, and the amount of grass carp cultured in cages is about 20g/ m2 to 25g/ m2. Some silver carp and bighead carp with the size of 200g/tail to 300g/tail can be cultured in cages with the size of100g/tail.

Fourth, pay attention to the way. Before the fry are put into the box, they should be bathed and disinfected to eliminate sparganium epidermidis and reduce the spread probability of pathogenic bacteria. Generally, it can be soaked in 3% ~ 5% salt solution or 20ppm potassium permanganate solution for 15 minutes. The time of free-range breeding is generally in late autumn or late winter, when the temperature is about 65438 05℃. At this time, grass carp can still eat after entering the box, and there is an operation recovery period, so it can eat early after early spring, which can improve the growth and development time of fish species and help to increase production and efficiency.

It is particularly important to strengthen the cage culture of grass carp in reservoirs. The key is to do a good job in the following aspects: (1) Check the box persistently. It is necessary to insist on daily unpacking inspection, regularly maintain the growth and development of fish species, effectively adjust feeding, carefully observe and analyze fish information, properly handle the problems found, keep a log of cage culture in reservoirs, and record daily temperature, food intake, feeding, fish death and diseases and insect pests. (2) Brush the box frequently. Brush the cage up and down once every 18 days to 15 days to eliminate the residual bait garbage and attached algae plants, so that the water quality can be fully exchanged. (3) Check the boxes on time. Check the cage frequently, and repair it immediately if it is damaged, so as to prevent fish from escaping or fierce fish from entering the cage. In the main flood season, it is necessary to immediately check the compressive strength of the rope lock, whether the rope is firm and whether the netting is deformed. (4) Switch the box frequently. With the rise and fall of the water level line of the water control project, it is necessary to adjust the cage to the appropriate position of the water level and water body.

To attach great importance to the prevention and treatment of fish diseases, we must first maintain a healthy body and mind and operate in accordance with technical specifications to prevent problems before they occur. Secondly, prevention and artificial immunization should be done well. Generally, the plasma inactivated vaccine against the "three major bacterial diseases" of grass carp and the plasma inactivated vaccine against grass carp hemorrhagic disease are injected before entering the box, and 0.2 ml ~ 0.5 ml of different species can be injected, and the species over 8 cm can be injected, mainly at the tip of dorsal fin and the base of ventral fin. At the same time, the fish must be disinfected with edible salt before entering the box, and also disinfected on time to prevent diseases. Feed bait for 3 ~ 5 days every 10 to prevent sparganosis in fish. Every 65,438+00 days to 65,438+05 days, 65,438+0.50-200g of quicklime powder is sprayed from each cage while it is hot to clean the water body.

Every month, pesticides and fungicides are spilled from the whole box. The method of hanging bags around the cage can be selected in high temperature season, and the medicine can be a mixture of bromochlorohydantoin, sodium thiosulfate and ferrous nitrate. In addition, it should be noted that green feed must be disinfected before feeding. Insist on feeding high-quality feed, and don't feed moldy and expired feed. Grass carp cultured in cages in reservoirs are generally prone to water mold, erythroderma, gill rot, colitis, hemorrhagic disease and so on. Please ask professional technology for correct diagnosis and symptomatic treatment when the disease occurs. It is not allowed to be ill or treated indiscriminately, and human factors lead to injury.