[Genetic analysis of the microevolutionary processes in cattle populations (the example of the B locus of blood groups)].

Dynamics of allele frequencies for the B-locus of blood groups in cattle populations and of a number of phenotype indexes in these animals was studied. It is determined that natural stabilizing selection and prezygotic selection, leading to a change in genetic structure, act in every population. The role of sires' influence on this process is insignificant.