Biological Characteristics of a Rare and Vulnerable Species (<i>SCHIZOTHORAX ARGENTATUS</i> (Kessler, 1874)) of TOKYRAUYN RIVER and Approbation of Its Artificial Reproduction

As a result of the complex impact of anthropogenic factors on the ecosystem of Balkhash Lake, the main commercial species of fish—endemic—Balkhash marinka was on the verge of extinction. Artificial reproduction is becoming increasingly important every year in the complex of works to maintain the commercial stocks of valuable fish species as well as to preserve rare and endangered populations. Despite the fact that attempts at artificial reproduction have been repeatedly made, to date no scientific and methodological basis has been created to study and preserve rare and endangered fish species in the Republic of Kazakhstan and there are no adapted technologies for the formation of repair herds of fish of this category for the fish breeding enterprises of the reproductive complex of Kazakhstan. The presence of a replacement stock of the Balkhash marinka will further contribute to the development and improvement of biotechnical methods for their breeding and cultivation of viable stocking material. The stocking of natural water bodies with viable fish seeds and the maintenance of living collections of rare and endangered fish species will contribute to their conservation in natural conditions and, as a reserve, in the country’s fish farms. The results of the development of effective technologies for artificial reproduction and the formation of a replacement stock of the Balkhash marinka in industrial conditions contribute to solving the fundamental problem associated with the preservation of rare and endemic fish species from complete extinction, genetic diversity and the rational use of the potential of natural populations. An analysis of genetic identification showed that the breeders of marinka, according to the results of sequencing the barcoding gene CO1 of mitochondrial DNA, belong to the species Balkhash marinka <i>S. argentatus</i> with an accuracy of 99–100%.