The impact of lateral localization of the procedure on the effectiveness of transplations of pre-implantation embryos in heifers-recipient

The article presents the results of a study of the efficiency of transcervical embryo transplantation obtained from donor- cows in vivo. The aim of the experiment was to compare the effectiveness of ipsilateral transfers randomized laterally from the uterine horn of embryos of different stages of development (blastocysts and morulas). The embryos were located in the left or right horn of the uterus of recipient heifers (n = 283 cows). It was experimentally established that the functional asymmetry of the ovaries of the recipients affects the level of survival of preimplantation embryos. Thus, in case of transfer to the left horn of the uterus of the recipients blastocysts 60.91% of pregnant heifers were found; morulas - 45.45%. In case of similar procedures in the right horn of the uterus - were found respectively 58.78% and 14.29% pregnant. The obtained results indicate the need for further scientific research to study the structural and physiological features that affect the survival rate of pre-implantation embryos.