How to cultivate the seedlings of herring in pond

Black carp is a kind of blue fish, mainly distributed in the plain area south of the Yangtze River in China, and rare in the north of the Yangtze River; it is an important fishery resource in the middle and lower reaches of the Yangtze River and lakes along the Yangtze River, and the main breeding object in lakes and ponds. It is one of the "four major domestic fish" in freshwater culture in China. In addition, in Anhui commonly known as "black mix","black mix" or "snail mix", because of its black body, like to eat snails named; northeast common "herring" is not herring, should be written "mackerel", is a deep-sea fish. In China, the largest herring specimen weighs 218 jin. It was caught in Jinniu Lake, Liuhe District, Nanjing in 2005. It is 1.86 meters long and weighs 218 jin. It is about forty years old after scale identification. Black carp also known as black, snail green. Osteichthys, Cyprinidae. The body is sub-cylindrical and the body is more than 1m long. Turquoise black, fins gray black. The head is broad and flat, the mouth is pointed, and there is no need. Pharyngeal teeth molar-like. Inhabit the middle and lower layers, staple food snails, clams, shrimp and aquatic insects. 4-5 It is sexually mature, lays eggs in the upper reaches of the river, and can be artificially propagated. It grows rapidly and its maximum weight is 70kg. The meat tastes good. It is the main freshwater fish culture object in China. It is distributed in all major river systems in China, mainly in the plain area south of the Yangtze River. Fish gall bladder is poisonous.

So how do you cultivate herring pond seedlings?

fry culture

Preparation of fry pond

1. Disinfection of fry pond: 15 days before putting fish in fry pond, the pond is cleaned and disinfected by medicine according to the concentration of quicklime 180 - 230 g/m3 or trichloroisocyanuric acid 3 - 5 g/m3.

2. Fertilization of fry pond: green manure shall be applied 5 days before seedling release, organic fertilizer shall be fermented and decomposed, and disinfected with 1%~2% quicklime; after fertilization 2 ~3 days, the pond water shall be deepened to 0.5 meters, and after 5 days, it shall be deepened to 0.6 meters ~0.7 meters. When water enters, it shall be filtered with 60 mesh dense net.

Seed Source

Fry obtained from breeding of qualified herring parent fish or purchased. Its quality shall comply with the provisions. Outsourcing seedlings shall obtain quarantine certificates from relevant departments. Breeding seedlings should be neat, healthy, disease-free and injury-free.

fry stocking

Select sunny days, put fry 5 - 7 days after hatching in the upwind; stocking density is 60,000 - 100,000/667 square meters; water temperature difference when putting fry shall not exceed 2℃.

feeding management

Feeding. After the fry are raised, they are fed with soy milk every day. The soybean dosage was 2 kg/667 m2 in the first 5 days after the fry was put in, and increased as appropriate after 10 days, twice a day, and the whole pond was sprinkled evenly.

During operation, the soybeans are first soaked in water for softening, that is, when the water temperature is about 25 DEG C, the soybeans are soaked in water for 5 hours to 7 hours, and then every 10 kg to 15 kg of soybeans are ground into 160 kg to 250 kg of soybean milk at one time.

Every breeding of 10,000 summer flower fish species with specifications above 3 cm requires 7 kg ~8 kg of soybean and bean cake and 30 kg ~40 kg of manure.

Patrolling the pond. Observe whether the activity status of fry entering the pond is normal. Where normal, the next pool fry immediately to swim around scattered, within 1 hour, can be observed fry activity traces, regular swimming, began to feed.

After breeding fry, patrol the pond many times every day, observe the water quality and fish activities, timely remove water centipede, frog eggs, weeds, Spirogyra, Hydrophytes, etc., check fry feeding, growth and diseases and insect pests, take measures in time when problems are found, and make records.

Water injection in stages. After a week of stocking, fry should be injected with water every 5 days to 7 days, deepening 10 cm to 15 cm each time. When the total length of fish reaches 3 cm, the depth of pond is kept at 1.3 ~1.5 meters.

Dragnet exercise. Fry after 25 days or so to grow into summer fish species, should be sparse pool. The net must be pulled before leaving the pool. Intensive exercise 2 ~3 times.

Prevention and treatment of fish diseases. In the early stage of fry breeding, fish diseases are less and enemies are more, but fish diseases increase in the later stage.

Fish diseases in the early stage of fry cultivation are mainly bubble disease, aquatic insects represented by water centipede, algae represented by Spirogyra, Hydrodictyon and Lake indigo, even macrozooplankton, aquatic grass and weeds in the water also constitute hazards to fry in the lower pond. In addition, wild miscellaneous fish, shrimp, snails, mussels, shellfish, tadpoles and so on are the enemy of fry.

At the later stage of cultivation, with the continuous growth of fish body and conversion of feeding habits, fish diseases gradually increased, such as common parasitic fish diseases such as trichodina, inclined tube worm, branchial cryptoflagellates, common bacterial fish diseases such as white-headed white-mouth disease and white skin disease.

Breeding of first-year-old fish

stocking time and stocking density

stocking time. When the herring summer flower fish species can be divided into pools after training, when the total length reaches more than 3 cm, it should be stocked in time, generally before the summer solstice.

stocking density. 5000 ~7000 herring species and 1200 ~1400 silver carp and bighead carp species were cultured on 666 square meters of water surface.

Feeding Management Feeding

Feed type. Black carp feed has soybean milk, bean dregs, bean cake paste, crushed snails, yellow clams and black carp feed, etc.

Feeding principles. Adhere to the "four fixed" feeding of "timing, positioning, quality and quantity":

Timing: feeding once every day from 8:00 a.m. to 10:00 a.m. and from 2:00 p.m. to 4:00 p.m.;

Positioning: Feed should be placed on a fixed feed table. After stocking, the fish should be sprinkled around the feed table first, and then gradually reduce the range to guide the fish to the feed table for feeding;

Quality: all kinds of feed should be comprehensive nutrition, clean, health, not to feed moldy deterioration of feed;

Quantitative: feeding should be appropriate and uniform, and it is advisable to eat the compound feed 2 hours to 3 hours after each feeding. In rainy days and when fish diseases are prevalent, the feeding amount should be reduced as appropriate.

Feed dosage. The breeding of green fingerling should be based on compound feed, and animal feed such as snail and yellow clam should be properly fed. Feed rates for breeding herring fingerlings are shown in the table.

The compound feed for feeding young fish should be mixed into paste or moistened into strips and thrown into the underwater slope of the pool or thrown on the feed table with fixed position. If the fish is mixed with pellet feed, it is also thrown on it, which is convenient for fish to eat and grow normally.

The proportion of feed per month to total feed was 3% in April, 4% in May, 5% in June, 15% in July, 23% in August, 20% in September, 15% in October, 10% in November, 3% in December and 2% from January to March.

daily management

Patrolling the pond. Daily management begins as soon as the species enter the pond. Through early and late inspection pond, observe water quality changes, fish dynamics, and take corresponding management measures, do a good job of production records.

Fill it regularly. Add new water every 15 days or so, each time the pool water deepens 10 cm to 15 cm (including partial water change), so that the water level remains about 1.5 meters.

Adjust feeding rate. Feed quantity and feeding frequency are regulated according to fish activity, feeding, growth and weather conditions. The satiety of fish should be controlled at 70%~80%.

Observe water color and adjust water quality. Should maintain the color is green brown, tea brown, transparency of 30 cm to 35 cm.

Disease control. Fish diseases should be detected in time and prevented early. Adhere to the principle of prevention over cure, do a good job of "three elimination", namely pond disinfection, fish species disinfection, feed platform (feed frame, food field) disinfection.

species selection

From the beginning of August, check the growth of all kinds of fish species every 10 ~15 days. If the specifications are very different, fish screening and separate culture should be adopted in time, and the amount of feeding and fertilization should be adjusted to ensure that all kinds of fish species come out of the pond with neat specifications.

Fish out of the pond, and pond

Species should be carefully verified and classified after screening and classification. When the temperature drops to 10℃~5℃, it should be stocked out of the pond, or collected in the pond, or transferred to the cultivation of second-age fish species.

Breeding of three-year-old fish

stocking density

Stocking density of two year old black carp species. 1000 ~1200 two-year-old herring species are generally put into each 667 square meter pond, 200 silver carp and bighead carp species are raised, 20 grass carp species are raised, and 200 crucian carp species (or 300 ~500 yellow pelteobagrus) are raised.

stocking density of three year old black carp. 380 ~420 three-year-old black carp species are generally put into each 667 square meter pond, 200 silver carp and bighead carp species are raised, 20 grass carp species are raised, and 200 crucian carp species are raised (or 300 ~500 yellow catfish).

feeding management

Feed animal feed and compound feed mainly, plant feed supplemented. Feed should be nutritious, fresh, in line with the provisions of feed hygiene standards. In the spring and autumn high incidence season appropriate increase digestible food, food field area should be larger. Keep the water fresh, disinfect food premises with medicines or use baits to prevent enteritis.