Method for obtaining batch American shad fertilized ova

Abstract

A method for obtaining batch American shad fertilized ova is characterized in that a plastic greenhouse cement pond is used for reserve parent overwintering culture, local fresh water is used, the salinity is increased gradually during water changing till the final salinity reaches 12%o to 15%o, the water temperature for overwintering culture is kept at more than 8 DEG C, and bait is NO.3 feeds of commercial freshwater fish expanded pellet feeds; parent spring intensive culture is between the end of March and the beginning of April, and as the temperature rises, two sides of the plastic greenhouse are used for ventilation, plastic film is dismounted, shading film is added, and the water temperature in a cement pond is kept between 16 DEG C and 18 DEG C; the salinity is reduced gradually each time water is changed, and the salinity is reduced by 2%o to 3%o each time till the final salinity reaches the salinity of local river water; parents for promoting spawning are selected to be put in curved spawning promoting channels between the middle of May and the beginning of June, the stocking density of the spawning promoting parents is between 0.8 shad / m<2> and 1 shad / m<2>, a natural spawning fertilization mode is used, the fertilized ova are collected in time after the parents spawn, the operation is performed in water, and the fertilized ova are moved to an incubating pond after counting.

Description

technical field [0001] The invention relates to aquaculture, in particular to a method for obtaining fertilized eggs of American shad in batches. Background technique [0002] American shad (Alosasapidissima), commonly known as American shad, is mainly distributed in the rivers and oceans of the Atlantic west coast of North America from Quebec, Canada to Florida, the United States. American shad is a reproductive and migratory fish. It is plump and plump, with delicious meat and high economic value. It has been widely introduced all over the world. In China, the Shanghai Fisheries Research Institute took the lead in introducing fertilized eggs produced by wild shad from the Mississippi River in the United States in 1998, and then hatched fertilized eggs, cultivated seedlings and cultured them. Because American shad is similar to Chinese shad in appearance and comparable in meat quality, American shad is also very popular with people when the Yangtze River shad is on the ver...

AI Technical Summary

Problems solved by technology

Due to the unique reproductive habits of this fish, at present, American shad breeding farmers use deep well water below 150 meters underground and with a stable water temperature of 16-17°C in winter and spring to carry out parental breeding of the fish, and then directly in the parental breeding ponds. The method of collecting fertilized eggs, but the underground deep well water resources are limited, and there are also geographical limitations, and many coastal cities have restricted the use of underground deep well water for aquaculture, and the existing method of collecting fertilized eggs in American shad adult fish breeding ponds The parameters are relatively blind, and the chance is relatively large, which limits the batch supply and large-scale production of American shad seedlings

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