Recent drastic advance in cryobiology/cryotechnology enables to enhance the commercial and research use of mammalian embryos. In this study, we conducted experiments to establish the efficient cryopreservation method for bovine oocytes and the embryos derived from in vitro fertilization. By using vitrification method, post-thaw survival rate achieved to 97% for IVF blastocysts and also high survival (72%)was obtained for oocytes. Moreover, hundreds of healthy calves have been delivered after transfer of the embryos cryopreserved at oocyte or blastocyst stages, respectively. These results demonstrate that the vitrification method in the present study can be a practical use of bovine oocytes and embryos.
