Pryshedko V. Oxen inseminators estimation after productive and reproductive qualities depending on the level of their stress resistance

Object of study: stress sires and Holstein breed their reproductive and productive characteristics. Objective: evaluation of sires for reproduction and productive qualities of their level of stress, to improve the effectiveness of their stud. Methods: zootechnical, ethological, physiological, histological, statistical and analytical. Theoretical and practical results: the theoretical level improved and generalized methodology to assess the productive and reproductive traits bulls of different levels stress. In practice - recommendations for the selection of bulls on their level of stress. Novelty: the first time experimentally shown to affect the level of stress on reproductive and productive characteristics of mature bulls of the Holstein breed. New data on semen quality and spermoproduktivnosti, histological and morpho-functional properties of the testicles and their appendages, depending on the level of stress. Degree of implementation: The results made for use in the Dnipropetrovsk regional state enterprise for breeding livestock. Scope of use - livestock, particularly dairy cattle.