Authors: O. S. CHECHENIKHINA, candidate of agricultural sciences, associate professor, O. G. LORETTS, doctor of biological sciences, professor, Ural State Agrarian University (42 K. Liebknekhta Str., 620075, Ekaterinburg)
Keywords: black-and-white breed, sire, line, productive longevity.
Abstract: Longevity, as a selection trait, deserves attention when evaluating sires, given the duration of the period of use of their daughters. The studies were conducted in a herd of black-and-white cows of Agrofirm Patrushi CJSC, Sysertsky District, Sverdlovsk Region. The studies analyzed data on 1037 animals born since 2007. When analyzing the reasons for the disposal
of highly productive descendants of manufacturing bulls (more than 30 thousand kg of milk over the entire life span), it was found that cows left the herd in most cases as a result of limb diseases (11.7–16.3 %), as well as the work of the digestive system (13.8–15.0 %). In this group, animals were not rejected due to udder diseases and difficult labor, which could affect their high productivity over the long term production use. Thus, in order to increase the period of production use of cattle, it is necessary to organize breeding and breeding work in enterprises, including through the assessment of manufacturing bulls.
