Determination of the optimum parameters of cattle embryos production in vitro from high-producing cows after their slaughter on a meat-packing plant was realized in the conditions of the Republic of Belarus. Oocyte cumulus complexes of cows of black-motley breed and the conditions of their maturing were used as the object of experimental research. Oocyte cumulus complex were allocated with dissection of ovaries tissue placed into Hanks culture medium. The search and morphological estimation of quality of received oocyte cumulus complexes were realized by microscopic research. Then, the oocytes were placed into a culture medium for cell maturing in СО2-incubator at 38,5 deg C with the maximum humidity (98%), with presence of 5% СО2 under a layer of mineral oil for 24 hours. Matured oocytes were impregnated with the frozen-thawed sperm after capacitation. Oogenesis efficiency of production of pre-implantation germs in vitro was determined in accordance with the level of embryonic fission and production of viable germs. Use cumulus cells monolayer made it possible to increase the quantity of ripened oocytes on 5,2-5,7%, level of embryonic fission - on 14,0-14,6% and production of embryos - on 13,8-12,5% depending on a way of its production in comparison with groups of the cells which were cultivated without a monolayer. Thus, the research has shown the exploitability of use of cellular reproductive technologies in selection and breeding activities in cattle breeding. Their application in combination with embryo transplantation could make it possible to use the reproductive potential of high-priced oocyte donors more effectively for the genetic improvement of animal population efficiency

Investigation of the efficiency of ethylene glycol and sucrose application in the capacity of cryoprotectors for cryopreservation of cattle embryos and their thawing in the conditions of application of saline solutions (as their dissolution medium) and nutritive media with a various structure was realized in the conditions of the Republic of Belarus. Research results showed that application of ethylene glycol in concentration 1,5 M and sucrose in concentration 1,0M proved to be the most effective. Regardless of the applied media the average safety of embryos was 93,8-96%, and acceptability - 59,3-62,5%. Peculiar feature of ethylene glycol use as cryoprotector for preservation of cattle embryos was that it could be quickly absorbed by a cell and quickly deduced from it. It made it possible to realize embryo transfer immediately after thawing. Application of ethylene glycol and sucrose as cryoprotectors could considerably simplify the procedure of transplantation of the frozen-thawed embryos, practically reducing it to a procedure of artificial insemination