Age-related variability in the stellate sturgeon domestication in industrial conditions

Abstract

Morphometric studies are fundamental in the domestication of new fish species. Despite the obvious dependence of the morphological parameters of fish on habitat conditions, they are currently used as the main criteria for the approval of breeding achievements, and a measure of the processes of domestication and selection. In this regard, we have begun work to study the variability of morphological characters in the process of domestication of stellate sturgeon (Asipenser stellatus, Pall) in a closed water supply. Researched sturgeon of Volga origin grown from caviar in artificial conditions in a closed water supply installation. At the first stage, 25 morphological parameters of stellate sturgeon underyearlings were studied. At the second stage, six years later, morphological studies were repeated in the same group of fish. Comparison of the average values of the indicators indicates the following trends in their change with the age of the fish: the relative length and height of the head, the rostrum (rr), and the diameter of the eye, the width of the mouth and the width of the break of the lower lip decrease; the indicators of the distance between the fins relative to the end of the snout and between themselves increase, the smallest and largest body height. At the same time, the most significant significant differences between underyearlings and six-year-olds were found in body height and head length. Similar changes are observed with age in most fish, including sturgeon. They are associated with the development of swimming muscles, physiological changes and demonstrate the expected biological age-related changes. The presented data on age-related changes in morphological parameters show the erroneousness of using sturgeon underyearlings as a control group for assessing uniformity and stability for distinctness.