Features of morphological variability of producers of variegated silver carp in the process of domestication

Abstract

The mottled silver carp is one of the best reclamation plants for eutrophic reservoirs. Since the middle of the last century, it has been widely acclimatized almost all over the world. Due to the fact that habitat conditions have a certain influence on the habitus of fish, a comparative analysis of the variability of the most informative morphological parameters, namely, length, mass, head length, body girth and their derived indices of the totality of individuals of variegated silver carp of varying degrees of domestication from the reservoirs of Romania and Russia with the first generation of domestication of fish from the Chinese population of unknown origin, was carried out. As a result of the research, it was revealed that the fish of the first generation of the Chinese natural population have a smaller head, and the weight, relative to the length of the body, is greater than that of the fish of the Ergenin, local and Romanian populations adapted to ponds in several generations. Comparison of local and Ergeninsky samples of fish indicates a tendency to deterioration of the index of physical development in the process of domestication and weakening of correlations between traits. The change in the indices of domesticated pond lines towards an increase in the relative size of the head and a deterioration in the index of physical development indicates the presence of selection for adaptation to conditions of low flow and restrictions in oxygen supply, and also causes a decrease in the commercial attractiveness of the pond mottled silver carp in the process of domestication. It is recommended when growing reproductive herds of variegated silver carp in ponds in the breeding program, in addition to breeding to consolidate technologically useful features, it is necessary to provide for selection to preserve the commercial qualities of fish.