Authors:
D. L. POSTNIKOV, post-graduate student,
South Ural State Agrarian University (13 Gagarina Str., 457100, Troitsk)
Abstract. Important direction of intensification of livestock is the correct organization of herd reproduction as well as introduction of biotechnological methods to quickly distribute and reproduce valuable genetic material. Transplantation method together with artificial insemination is considered as the basis of modern biotechnology for reproduction of highly productive breeding animals. The technology of transplantation of embryos involves a series of sequential stages: the selection of donors; carrying out of superovulation in donors; the selection of manufacturers and insemination donor; extracting embryos and evaluating them; culturing or freezing of embryos; selection and training of recipients; transplantation of embryo to the recipient; evaluation of the results of transplantation. Comparative characteristics of reproductive ability of cattle produced by embryo transfer using recipients of various breeds are presented in this paper. For the studies were selected cows, received by a method of transplantation of embryos (“embryos”) using recipients of Hereford (n = 24) and Simmental breeds (n = 94) in identical conditions of feeding and maintenance. After analyzing the researched data, it was found that reproductive ability of cows, received by a method of transplantation of embryos, is retained. In addition, indicators of reproductive capacity of “embryos” are slightly higher than that of cows, obtained in a natural way. When comparing groups of “embryos” grown on different breeds of recipients, the leading position in terms of reproductive capacity was occupied by animals, obtained by the method of transplantation of embryos using recipient Simmental breed. Age of first calving in cows of all groups was within the recommended timeframe and did not go beyond the physiological and zootechnical norms. The optimal duration of service period was recorded on “embryos” grown in the recipients of Simmental breed; “embryos” grown in the recipients of Hereford breed, and the descendants obtained in a natural way exceeded this target by 6 and 11.8 days, respectively. Milking “embryos” grown in the recipients of the Simmental breed showed higher milk yield than the cows of other groups. Overall, when comparing the groups of “embryos” grown in different breeds of recipients, the leading positions on indicators of reproductive ability were occupied by animals obtained by embryo transfer using the recipient of the Simmental breed.
Keywords: reproduction, biotechnological method, offspring, Simmental, Hereford, embryos.
