COMPARATIVE CHARACTERISTIC OF GENETIC PARAMETERS OF D -SYSTEM BLOOD GROUP OF NOVOALEXANDROVSKAYA DRAFTER AND TORIAN BREEDS STALLIONS

Abstract

In Ukraine, the Novoalexandrovskaya and Torian drafter horse breeds belong to breeds with a limited genetic resources. This creates a problem of conservation and efficient breeding of these breeds. One of the priority tasks of modern work with the Novoalexandrovskaya drafter and Torian horse breeds is to preserve the unique genetic resource, improve breeding qualities and working efficiency. Therefore, it is relevant to study the genetic features of these breeds. The article presents the results of research of the immunogenetic structure of Novoalexandrovskaya and Torian horse breeds of different farms of Ukraine on D-system of blood groups. The aim of the work was to identify genetic markers inherent in the Novoalexandrovskaya drafter and Torian horse breeds, which make it possible to solve breeding and genetic issues in the preservation and improvement of the breeds. A high frequency of alleles was found in Novoalexandrovskaya drafter horse breed, there are Ddg (0,230), Dad (0,202), Dde (0,174), Dd (0,115). The alleles Dcgm (0,080), Dbcm (0,048), Ddk (0,024), Dcеgm (0,017) Dd (0,015) were found relatively less common. The allele Dcegm (0.017) was the rarest allele among the Novoalexandrovskaya drafter horse breed and it was 14.78% less common than the allele Dd (0.115). The Torian horse breed has the high frequency of occurrence of alleles Dcgm (0,25), Dd (0,112) Ddg (0,097), Dbcm (0,073), Ddk (0,225). Less common alleles are Dde (0,048), Dcеgm (0,016), Dad (0,032). The actual degree of homozygosity of Novoalexandrovskaya grafter horse breed is G (0.132), the expected degree is Ca (0.148), the Torian horse breed degrees are G (0.064) and Ca (0.144) accordingly. The polymorphism level of Ae of the breeds is 6.75 and 6.919 accordingly, indicating homozygote deficiency and low level of consolidation. The actual degree of heterozygosity of Novoalexandrovskaya drafter horse breed is 0.867, while the expected degree is 0.871. The actual degree of heterozygosity of Torian horse breed is 0.935, while the expected degree is 0.855. Thus, the level of genetic diversity in the examined horses is rather high, which indicates a significant reserve of variability and avoids innbreeding depression. Keywords: allele, horses, Novoalexandrovskaya grafter horse breed, Torian breed, genetic frequency, genetic variability.