The genetic polymorphism of the pike perch Sander lucioperca, sampled on the territory of the Republic of Kazakhstan (Lake Balkhash, Urals River, Syrdarya River and Shardara water reservoir, North Aral Sea) and in the Volga River, and the bersh Sandler volgensis (Lake Balkhash, Volga River) populations was examined at six microsatellite loci and the mitochondrial DNA cytochrome b gene. All examined loci were successfully amplified in both species and produced quite different allele profiles, which allows them to be used for accurate species identification of pike perch and bersh. At the same time, neither nuclear nor mitochondrial markers revealed statistically significant differentiation between the examined pike perch samples, excluding some isolation of the population from Volga River.

Purpose: Review the experience, principles and parameters of the sturgeon assessment quality by anomalies in early ontogeny. Results: Maintaining the number of sturgeon fish in the transboundary Caspian Sea is provided by five states (Russia, Iran, Azerbaijan, Turkmenistan, Kazakhstan) at 16 Sturgeon hatcheries, where their artificial reproduction is carried out. FAO recognizes Russia’s leadership in creating the basic technology for the sturgeon artificial reproduction, but the other four Caspian states also make a significant contribution to its modern optimizations. There is almost a century of tradition behind the technological development of artificial reproduction in sturgeons. During the artificial reproduction of sturgeons, anomalies in the structure and functions may occur, such as deformities, defects in organs and tissues, edema, hematomas, etc. The sturgeon anomalies classification is based on structural and functional principles. Identification of anomalies is carried out on the basis of a previously created classification, divided into nine large classes. Identification of sturgeon anomalies during the period of their artificial reproduction makes it possible to clarify the real value of replenishment of their stock. Methods: Analysis of professional scientific literature and practical guides. Conclusions: The presence and number of Sturgeon anomalies make it possible to determine their death percentage to calculate the real number of replenishment of the Caspian Sturgeon stock.

This review represents the dynamics of the locations and number of sturgeon spawning grounds in the Ural (Zhaiyk) River for almost a 150 years with details for the beginning of the current century. The geographic, hydrographic and hydrochemical characteristics of the Ural River are given. The state of the 68 previously known spawning grounds of the river’s lower damless flow between the city of Atyrau (former Gur’ev city) and city of Uralsk at a distance from 70 up to 796.5 km from the river mouth have been evaluated. Most of them currently have been lost or are in critical conditions due to meandering of the riverbed, the prevalence of low-water years, and the decreasing quality of the spawning substrate (silting; overgrowing with shrubs, woody, hard herbaceous, and higher aquatic vegetation). The area of spawning grounds, depth, flow velocity at the river stations, water temperature, type of substrate, and the degree of overgrowth and weediness have been determined. On the territory of the Republic of Kazakhstan in the lower reaches of the transboundary Ural River, only a few classic sturgeon spawning grounds have been preserved (including: Naidenovskoe, Nizhnee Barbastovskoe, Yablonevoe, Politovskoe, Inderskoe, and Yamankhalinskoe). The proportion of operating spawning grounds is 11% of those previously documented. A map-scheme of the location and topography of the remaining spawning grounds of the lower reaches of the Ural River is presented.

Common carp (Cyprinus carpio) is a widespread freshwater fish species of the Cyprinidae family, one of the largest and most diverse fish families. The natural habitats of C. carpio extend from Western Europe to South-East Asia. Common carp has remained an economically important fish species in aquaculture for many centuries and its production nowadays exceeds 4 million tons worldwide and continues to grow. The taxonomy of C. carpio is complicated, since this species is usually distinguished in two, three, and even four distinct subspecies. In the present study, we used ddRAD-sequencing to genotype 30 specimens from five wild common carp populations from the Ponto-Caspian, Balkhash-Ile, and Aral Sea geographical regions. It is demonstrated that they differ at the population level according to F-statistics analysis. At the same time, the subspecies status of C. carpio aralensis has not yet been confirmed. We found several loci that can be used as a discriminant for Aral and Ponto-Caspian wild common carp populations. It is suggested that Aral carp (C. carpio aralensis), which inhabits Balkhash-Ile and Aral Sea basins, is related to Ponto-Caspian or European carp (C. carpio carpio). Moreover, Aral carp might be the ancestor for European carp subspecies. Our results can be used to develop population-specific, high-density SNP marker panels, allowing the trade control of common carp production in the Eurasian Economic Union.

The article presents the analysis of biological parameters of parthenogenetics of Artemia crustaceans of the hypergaline reservoirs of Kazakhstan. In the lakes under study there are shown the changes of the total crustacean biomass decreasing from high-productive to low-productive. Most of the reservoirs with Artemia in Kazakhstan are characterized by the presence of Artemia parthenogenetic populations with the absence or extremely small presence of males. The aggregation of males in significant numbers may indicate the tension of the ecological situation in the reservoirs and the desire of the population to increase the survival and stability of the offspring. It has been stated that all age periods of crustacean maturation are found in the reservoirs. At the same time, the basis of Artemia populations in all studied lakes are the youngest stages - nauplius, which form 53-86% of the total number of Artemias. In lakes Artemia crustaceans are presented by bisexual parthenogenetic race, with all age stages of development during the summer - autumnal period of observations. The hydrochemical mode of hypergaline lakes of Karabassky floods is favorable for activity of Artemia Branchiopoda crustaceans. The size of crustacean biomass populations in Lake Balhash change on seasons ranging from low to very high. Lake No. 1 is highly productive in Artemias in the summer, and lake No. 2 - in the spring. Such difference in temporary aspect is caused by existence of various generations in the populations of the crustaceans on seasons. The data obtained prove the high potential of the studied small reservoirs of the Balkhash region in relation to autumn plankton cysts