The effect of two-stage vitrification on the viability of cow embryos obtained by different methods

The theses present the results of studies of the effect of two-stage vitrification on the survival of embryos of cattle of the Ukrainian red-speckled dairy breed obtained by in vitro and in vivo methods. In the course of research, it was established that the development of cattle embryos obtained in vivo after two-stage vitrification was better than the development of cow embryos obtained outside the body (32.6% - 28/86 versus 6.9% - 5/72, p<0.001). It was established that the expanded blastocyst stage, emerging from the zona pellucida, reached 20.9% (33/158) of all thawed embryos after their two-stage vitrification obtained by both methods, the blastocyst stage emerging from the zona pellucida reached 32.3% (51 /158).