Interbreeding usage in order to improve Russian livestock in recent decades has become widespread. At the same time, an extremely high heterosis effect was established, which is demonstrated in higher productivity parametres of the cross-breeding cattle in comparison with the initial breeds. The aim of this work was to identify heterosis share effect by maternal and paternal basis factors, the blood level of the improving breed, as well as complex environmental effect of the "year of lactation" in the overall effectiveness of selection measures associated with crossbreeding. It was found that the share effect of the improving breed practically does not change for all genotypes and ranges from 0.39 to 0.44 depending on the genotype. The share effect of maternal breed is minimal in the group of animals with Holstein breed blood content of 50% and is 0.15 and it is maximum in the variants of backcrossing.

АннотацияВ статье рассмотрены вопросы применения иммуногенетических характеристик крупного рогатого скота для усовершенствования методов оценки генотипа племенных животных. Выявлены аллельные варианты групп крови базового генофонда крупного рогатого скота ярославской породы имеющие наибольшую связь с молочной продуктивностью.Ключевые слова: крупный рогатый скот, генотип, селекционный индекс, наследуемость, регрессия, продуктивность. AbstractThe article deals with the application of immunogenetic characteristics of dairy cattle to improve methods for assessing the genotype of breeding animals. Allelic variants of blood groups of the basic gene pool of cattle of the Yaroslavl breed having the greatest correlation with dairy productivity are revealed.