Evaluation of the genetic variability of pedigree stocks of amur carp (Cyprinus rubrofuscus Lacépède, 1803)

Purpose. To study the genetic peculiarities of pedigree tocksof Amur carp and evaluate its genetic variability by analyzing distribution of alleles and genotypes by the specific protein systems and cytogenetic parameters. Methodology. Analysis of polymorphism of protein systems was performed using electrophoresis in polyacrylamide gel. As protein markers to evaluate the genetic structure of Amur carp stocks, the separation of allelic and genotypic frequencies by loci, which encode a number of fish blood proteins, were used: transferrin (TF), albumin (ALB) and esterase (EST, 3.1.1.1). Cytogenetic analysis was performed using the micronucleus test and analysis of apoptosisfrequencies. Collection and processing of biological material of fish as well as statistical processing of the obtained data was performed using generally accepted methods. Findings. A comprehensive analysis of the genetic structure of Amur carp from three farms in Ukraine was carried out by protein systems and cytogenetic markers. The results of the study showed that all pedigree groups of Amur carp were characterized by a deviation towards the predominance of heterozygotes (Fis = from –0.084 to –0.344). A minimal imbalance was observed in the group of carp from the farm “Karpatskyi Vodogray” LLC (Fis = –0.084). The maximum violation of the genetic balance was found in carp from the farm of JSC “Sumyrybhosp” (Fis = –0.308) and in the group from the experimental farm “Veliky Lyubin” (Fis = –0.344). In general, the analysis of the protein systems of fish blood showed a high level of heterogeneity of pedigree stocks of Amur carp from different farms in Ukraine. The analysis of frequencies of cytogenetic parameters of Amur carp from three fish farms showed that fish from fish farms of JSC “Sumyrybhosp” and PFE “Dzherelo” were characterized by a lower frequency of erythrocytes with micronuclei (EMN) (3.3±0.3 ‰), (3.2±0.3 ‰), lymphocytes with micronuclei (LMN) (2.1±0, 2 ‰), (1.9±0.2 ‰), and apoptosis (4.2±0.3‰), (4,3±0,3‰) compared to the group from fish farm “Karpatskyi Vodogray” LLC, where these values were as follows: EMN (4.7±0.3 ‰), LMN (2.4±0.2‰), apoptosis (5.6±0.4‰). These results indicates a lower level of destabilization of chromosomal apparatus of Amur carp from the fish farm JSC “Sumyrybhosp” at the time of the study. Originality. A comprehensive evaluation of the level of variability of the genetic structure of pedigree stocks of Amur carp from different regions of Ukraine was performed for the first time. Practical Value. Pedigree socksof Amur carp have important practical value in selective breeding work with carps, including works for obtaining hybrid lines to increase the resistance of breeding material. Keywords: Amur carp, genetic structure, locus, alleles, genotype, heterozygosity, micronucleus test, cytogenetic analysis.