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Fish-breeding, biological and production characteristics of first- and second-generation carp hybrids of breeding

A comparative analysis of the fish-breeding and production characteristics of first- and second-generation carp hybrids obtained from crossing local mongrel females with males of the intra-breed type of the Moscow scaly pair carp was carried out. As a result of parallel cultivation of five variants of crossing carp to their puberty with further verification of breeding value for offspring, a promising hybrid (♀Me × M♂) was selected, with which breeding work was carried out for two generations. A comparison of the fish-breeding biological and production characteristics of twogeneration carp hybrids revealed the best indicators for all the parameters studied in the first generation, which, apparently, is associated with the phenomenon of heterosis. Producers of carp hybrids for three years of work with them (4–6-yearolds) had a more pronounced fertility in the production of oocytes in first-generation females, both in terms of working and relative fertility. As for males, there were no significant differences in the one-time volume of ejaculate, concentration and degree of sperm motility in hybrid individuals of two generations of carp in studies. The exterior indicators of carp hybrids according to the high-spin index in the first generation exceeded the same indicator in the second generation. The additional calculation carried out for the variation of the analyzed indicators revealed slightly lower values of the coefficient of variation in the second generation among different age groups of carp. This situation of the emerging tendency to decrease the spread of the analyzed indicators in relation to their average values can be explained by the effect of stabilizing selection in the second generation of the hybrid carp. According to the results of the study of the fish-breeding, biological and productive characteristics of two generations of carp hybrids, a return crossing with an improver breed (Moscow scaly) was performed.