Fry propagation
The accessibility of bream matures at the age of 2 ~ 3, and the breeding season is a little later than that of carp and crucian carp and a little earlier than that of domestic fish. Most of the middle and lower reaches of the Yangtze River are in 4
sweep
From the end of the month to the beginning of June, that is, the season when the water temperature is 20 ~ 29℃ is the spawning period. In lakes and places where aquatic plants flourish, fertilized eggs are sticky and develop on aquatic plants or other objects. In the breeding season, if there is slight running water or other conditions, the parent fish of Megalobrama amblycephala cultured in the pond can cause unconcentrated natural spawning. Therefore, after the spring of each year, male and female parent fish should be cultivated separately, and then estrus should be artificially induced and propagated in batches to produce fry.
Artificial propagation of fry can adopt natural spawning or artificial spawning. It is best to breed parent fish in ponds for one year, or directly select them from natural water. It's easy to tell the sex of snapper. From the fingerling stage, the first fin of female pectoral fin is thin and straight, and the thickness of male fish is "wavy". After sexual maturity, there are dense "pearl stars" on the back of the first few fins, the back of the tail stalk and the abdominal edge of the male pectoral fin, and the abdomen feels rough when touched by hand, and the abdomen is small, and milky semen flows out from the abdomen after gentle pressure; The female fish only has a small number of "pearl stars" on the orbital bone and back, and her abdomen is swollen and soft. When breeding, mature parent fish can be selected and combined into spawning ponds as planned, or artificially induced by hormones to naturally spawn and fertilize them. Due to snapper
Fish eggs are sticky, which can be attached to the artificial waiting fish nest and then hatched in still water. You can also use artificial egg collection for fertilization, then debond the fertilized egg and then carry out mobile artificial incubation. Its feeding process and operation method are basically the same as those of carp.
grow seedlings
The bream fry is small and delicate, so be careful when operating. The water quality of fry should not be too fat when entering the pond, and it should not be too crowded when leaving the pond. The method of grading feeding is commonly used to cultivate fry into spring seedlings.
After hatching for 2 ~ 3 days, the fry gradually separated from the fish nest and began to eat small zooplankton. Therefore, when the fry enter the pond, they should be properly fertilized every day. It is suitable to put12 ~150,000 fry per mu for debonding incubation. When the fry begin to eat, it is best to feed the egg yolk 1 ~ 2 times, then feed soybean milk for a few days, and then decide the amount of fertilizer according to the water quality and fry growth. After 15 ~ 20 days of feeding, fry can grow to 2 ~ 3 cm, and then feed in different ponds.
sweep
For the second time, the pond was divided into different ponds for sparse cultivation, and 40,000-50,000 fish species were put in each mu. Farming is mainly based on fertilization and plankton farming. At the same time, you can feed bean cake pulp every other day, and you can also add some plant feeds such as Elsholtzia and duckweed. Summer flowers with a size of 4 ~ 5 cm can be cultivated in about one month, and the survival rate can reach about 80%. Winter fingerlings developed from summer flowers, that is, three-level feeding. The method is basically the same as that of raising grass carp. The transparency of the pool water is generally maintained at about 30 cm. Generally, the stocking density is 5000 ~ 7000 per mu, and silver carp, bighead carp and herring summer flowers are cultured together with kloc-0/0 ~ 20%. 10 ~ 20% of Megalobrama amblycephala can also be kept in the main breeding ponds of silver carp and bighead carp. Feed sedge, duckweed and bean cake pulp before feeding duckweed, clover or chopped fresh hay. Generally, it can grow to 12 ~ 15 cm in winter, and the survival rate can reach over 90%. Fish farming in the second year.
Adult fish culture
Cultivation methods include pond main culture or mixed culture, coarse culture on the surface of lakes and reservoirs rich in aquatic plants, intensive culture in cages, etc. Ponds with water depth1.5 ~ 2m can put 600 ~ 800 overwintering fish species per mu, and 200 ~ 300 silver carp and bighead carp can be mixed, and the megalobrama amblycephala can reach about 500g a year. Its growth rate is faster before the third instar. Then it gradually slowed down. The feeding habit of bream is similar to that of grass carp, so it can economically use the bait resources in natural waters and also eat artificial feed to promote the growth of adult fish. The experimental pond in Wuhan mainly raises bream, and the effect is good. The method is as follows: 1220 mu with a tail weight of 40g for wintering bream, 200 for silver carp with a tail weight of 50g, and 30 for silver carp with a tail weight of 60g; some high-backed crucian carp are appropriately put in and "Zheng Da" is used. Pay attention to water quality management at ordinary times to prevent water quality from deteriorating and flooding, and the dissolved oxygen in the pool water is not less than 2 mg/L day and night. At the end of the year, the yield per mu was 500 Jin, including 350 Jin of anchovy, with an average tail weight of 0.35 Jin.
Feeding method
The bream is called bulbous bream because of its flat body and small round head. Megalobrama amblycephala is plump, delicious in meat and fast in growth, up to 3 kg. Megalobrama amblycephala is also a herbivorous fish, and its main foods are vascular weeds, POTAMOGETON crispus and black algae. Young fish will eat some animal feed during their development. China Organic Agriculture Network