Морфофизиологические особенности популяции русского осетра Волго-Каспийского бассейна

The object of the study is Russian sturgeon Acipenser gueldenstaedtii of artificial generation grown in hatcheries of the Astrakhan region, and manufacturers of Russian sturgeon, caught in the natural conditions of the Caspian Sea at the II and III stages of gonad maturity in 2014-2015. To assess the physiological status of fish, a set of morphological and physiological indicators (absolute and relative weight of heart, liver, spleen, gonads) was used. The received values of cardiosomatic, hepatosomatic, gonadosomatic indices and spleen index showed that juveniles produced by modern hatcheries, do not meet the basic requirements for quality. This suggests that the replenishment of natural stocks from factory generating juveniles will not be significant. During the study of morphological features of Russian sturgeon in the marine life for the period 2014-2015 there was revealed a decline in the values of most indicators compared to the '70s, that is probably due to a decrease in the number of producers of natural sturgeon generations. The installed variability of cardiosomatic, hepatosomatic, gonadosomatic indices and spleen index is seasonal, which corresponds to the seasonal characteristics of the physiology and biology of sturgeon. Specialists of hatcheries of the Astrakhan region should keep sturgeon population variability, when working with producers of all the biological groups; it will enhance the quality of the offspring.