Breeding techniques and matters needing attention of common carp in spring

Spring is the key season for carp breeding. However, if the carp is not properly managed, the reproduction rate of carp will be low. There are five main reasons for the low reproduction rate of carp: first, the maturity of species is not enough, the spawning is less, and the fertilization rate is low. Second, the fish eggs are moldy during incubation. Third, it is affected by cold air and plum rain during the incubation period. Fourth, the hatching pond is not thorough enough, leaving the natural enemies of fish fry. Fifth, the daily management of carp fry after emergence can not meet the requirements. In view of these reasons, the following three points should be done to improve the reproduction rate of carp:

Carp

1. Choose good carp and parent fish. Should choose more than 3 years old, weight 3 to 5 kg female fish; choose more than 2 years old, weight 1.5 to 2 kg male fish. In the non-breeding season, females and males should be raised in separate ponds for daily management, especially to avoid some early mature fish spawning in the same pond. Daily regular, fixed-point, quantitative feeding of concentrate feed (such as peanut bran, soybeans, corn, etc.), the general feeding amount is 2% Mel 3% of the body weight of parent fish.

2. The reproduction of carp. When the water temperature in the pond rises to more than 18 ℃, the carp can reproduce and hatch. The spawning pond and the hatching pond should be ready before the carp are paired, and if the water quality is fresh, the fish can be netted in the breeding pond, and the breeding fish can be selected and paired. If there will still be cold air invasion, do not pull the net. Choose the female carp with a swollen, soft and elastic abdomen to breed, put them into the spawning pond according to the female-to-male ratio of carp at 1:5, and set up a square fish nest with bamboo poles at the inlet of the spawning pond. The size of the nest depends on the number of parent fish, with clean and sterilized water hyacinth in the middle. New water is injected every day to stimulate carp species to estrus and spawn. After spawning, the water hyacinth attached to the eggs was disinfected to reduce the occurrence of water mildew during hatching. After disinfection, the fish eggs are transferred to a prepared incubator to hatch. In order to reduce the trouble of turning fish fry into ponds, about 300000 fish eggs can be placed per mu.

3. Hatching of carp eggs and cultivation of fish fry. If the fish eggs encounter cold air or rainy weather after putting them in the incubation pond, cover the fish eggs with straw or film or increase the depth of the pond water accordingly. Generally speaking, the fry will emerge from the film in about 7 days, but the temperature will lead to the phenomenon of advance or delay. Wait until the carp fry have the ability to swim, then take out the nest, but you must pay attention to cleaning the water hyacinth in the nest to prevent the fry from being cleared out with the nest. Fish fry within 3 to 5 days after film removal can be fed with about 2 kg of soybean milk or fermented peanut bran per mu. As the fry grows up, you can also gradually increase the amount of dung water or feed the carp with fermented chicken and pig manure. Dragging ponds with branches can be used once or twice a day to improve the activity of carp fry. Every morning, we should also pay attention to observe whether there is a phenomenon of floating head of fish fry in the fish pond. if so, we should inject new water into the culture pond, or wait until there is no floating head, and then divide the pond to reduce the density of fish fry, generally putting 100000 to 200000 carp fry per mu. Gradually add 10 centimeters of fresh water to the pool every week. With the increase of fish fry, carp fry can be gradually sold in ponds.