Vestnik OrelGAU, 4(49), August 2014 UDC 636.082 SIRE INFLUENCE ON REASONS OF DAUGHTER CULLING FROM THE HERD Syrtseva Е. <...> М., Post-graduate student Shendakov A.I., Doctor of Agricultural Sciences Orel State Agrarian University, Orel City, Russia E-mail: bio413@ya.ru, Phone: 8-953-816-78-84 ABSTRACT The article presents the results of bull’s evaluation on susceptibility of cows to culling reasons, including udder, legs and internal organs diseases, surgical diseases, tuberculosis and etc. <...> It has been found out that bulls are able to have a significant impact on the reasons for culling heifers from the herd. <...> More than that, heifers are able to inherit through their fathers their maternal ancestors’ resistance to gynecological diseases. <...> The majority of sires (Buyan 114, Rom 1675, Dobryak 1745 and Dar 2383) has 20,6-27,6 % of culled heifers with gynecological diseases in the livestock structure, although gillyf-lower sires have only 8.3% of heifers 1206 culled for the same reason. <...> Buyan bulls have ap-proximately 7,5% of heifers culled for old age, sire Dar 2383 have 3,7 and 4,9% of heifers accordingly culled for leucosis and tuberculosis. <...> KEY WORDS Black-and-White and Holstein cattle; Sires; Breeding; Culling reasons; Diseases. <...> Due to the high milk production and acclimatization abilities unit weight of cows of black-motley breed in our country has significantly grown over the last ten years. <...> However, despite a number of advantages, black-motley breed of cattle needs to improve its productive and technological features. <...> Holstein genotype has been widely used to improve this breed for several decades already since the former is closely related to the latter and quite common in the United States, Canada, Germany. <...> Crossbred cows have high productivity, suitable for machine milking udder, but at the same time they have low rates of life expectancy and reproductive qualities. <...> These animals usually distinguish in intensive metabolism and in rapid outflow of the herd. <...> Premature culling of cows from the herd reduces the estimation reliability for productivity and breeding qualities, since they do not give a large number of descendants. <...> Moreover, owing to gynecological diseases, which greatly impede productivity of a herd, farms <...>