Structure of the STR allele pool of the population of kholmogoryk breed bulls, saved in the Komi Republic of the bank of frosed semen

Microsatellite polymorphism was studied in 162 purebred Pechora-type bulls of the Kholmogory, Kholmogory, and Holstein breeds, as well as Holstein-Kholmogory crossbreeds. For 15 microsatellite loci, 132 alleles were identified, or 8.8 on average per locus. Of the total number of alleles, 78 (59.1%), or 5.2 alleles per locus on average, occurred with frequencies greater than 0.1 in at least one of the groups of bulls of different genealogy and breed. Twenty-one alleles in 13 loci occurred with frequencies of 0.15 and higher, regardless of the breed, genealogy, and breed of the group. The largest number of alleles was found in the Pechora-Kholmogory-Holstein and Kholmogory-Holstein crossbreeding groups. The maximum genetic distance was established between the crossed Pechora-Kholmogory bulls and Holstein bulls (DN 0.237, FST 0.045). High genetic differentiation of Holstein bulls with crossed and purebred Pechora-type sires of the Kholmogory breed was confirmed by cluster analysis. The genetic difference between the classical Kholmogory breed and the Holstein was lower. Cluster analysis of the results of genotyping by microsatellites of Kholmogory bulls in one array with samples of Holstein animals and Kholmogory-Holstein crosses made it possible to obtain additional information for planning measures to maintain the genetic diversity of the seved herd of purebred Kholmogory cattle.