title: The combinational ability of genotypes in terms of reproduction in different climatic zones of the Russian Federation
abstract: This article presents the results of a study of the reproductive characteristics of Holstein cattle bred in four different climatic zones of the Russian Federation: subtropical, temperate continental, sharply continental, and Arctic. The study analyzed a sample of more than 14 thousand first-calf heifers. The main purpose of the work was to study the combinational ability of various lines of the Holstein breed according to key reproduction indicators, such as the age of the first calving, the ca
journal: BIO Web of Conferences