[Variation of the BoLA-DRB3 gene in dairy cattle and its effect on the viability parameters].

Genotyping of the BoLA-DRB3 alleles was performed in dairy cattle of Krasnodar krai and Holstein stud bulls. Loss of heterozygosity, which decreased the reproductive parameters, was observed. It was proposed that stud bulls be selected on the basis of their genotyping at the BoLA-DRB3 gene to prevent further decay of cattle viability.

[Possible causes and consequences of the spread of individual allelic variants of the BoLA-DRB3 locus in groups of Holstein and Ayrshire cattle].

The frequencies of polymorphic variants of the BoLA-DRB3 locus have been estimated in groups of Holstein and Ayrshire bull sires. Considerably increased frequencies of individual alleles have been found in some groups of cattle, depending on the breed and breeding value. The possible causes and consequences of the observed relationships have been analyzed.