DefinePK

Abstract

In recent years, local cattle populations have been replaced by highly productive breeds in the Republic of Kazakhstan, which has significantly reduced the number of local breeds. Today, two cattle breeds are on the verge of extinction, one of which is the Alatau breed, which was bred in 1950 by crossing local aboriginal Kazakh cattle with Brown Swiss cattle brought in together with immigrants from Russia. In this regard, the purpose of our work is to obtain new genotypes by backcrossing, i.e., the use of sperm from purebred bulls of the Alatau breed on high-blooded animals of the Brown Swiss breed, followed by a study of the offspring obtained for development and milk productivity in comparison with the descendants of heifers from the Brown Swiss bulls. Upon completion of the research, it was established that heifers obtained from Alatau bulls in all growth periods exceeded the indicators of heifers obtained from Brown Swiss bulls by 14.9kg at 6 months, 17.3kg at 12 months, and 16.8kg at 18 months. It was also found that the daughters of the Alatau bulls were inseminated 52 days earlier than those received from the Brown Swiss bulls. As a result, they experienced their first calving 48 days, or approximately 1.6 months, earlier than their counterparts. There is no significant difference between the indicators of milk productivity of the daughters of Alatau and Brown Swiss bulls.