Assessment and preservation of the gene pool of the domestic Kholmogorsk cattle breed in the Arkhangelsk region

The article presents the results of monitoring immunogenetic studies on the origin of Kholmogory cattle to establish their breed genetic passport for the EAB locus of blood groups. The importance of determining of the breeding animals statute taking into account the forms of the identified state of erythrocyte antigens for the purpose of registration in the federal state information and analytical system of breeding resources of the Russian Federation is noted. In breeding farms of the Arkhangelsk region over the past 29 years, the total number of animals tested for the reliability of origin was 57,311. The percentage of reliability in the monitored livestock numbers varied from 86.95% (1995-2000) to 97.28% (2016-2020). To establish the genetic passport of breeding female tribal species of the breed with up to 75% Holstein bloodline approved for breeding purposes when working with Kholmogory cattle, we conducted immunogenetic testing, which revealed 46 alleles of the EAB locus. The total frequency of the EAB locus alleles in animals of groups 1-2 with specific (typical) for the Kholmogory breed and with unique alleles was 69.38%. In group 3 of animals with alleles of the approved Holstein breed, the total frequency was set at 30.6%, in group 4 with alleles of unapproved breeds – 0.02%. It was established that the concentration of alleles G2O2, B2O2, B2G2KA’B’G’O’G’’, B2E’2G’, B2O2Y2D’, Q is very low, they are found only in some individuals. The degree of homozygosity (theoretical) is 5.6%, the number of effective alleles is 17.9.