[In vitro embryo production from oocytes from ovaries of a single slaughtered cow]

This communication describes the in vitro maturation and in vitro fertilization of bovine follicular oocytes. Further development of the embryos was achieved by using a granulosa cell culture system. The in vitro development of oocytes to morula/blastocyst stages obtained from individual cows was compared to the results of pooled simultaneous cultured oocytes and to our over-all results of this method. While there were no statistical differences in the developmental rates between these three groups (individual cows: 28.1%, simultaneous pool: 34.0%, over-all results: 32.7%) marked differences were found between the 22 animals investigated separately. These results indicate that there were great individual variabilities due to the oocyte population comparable to the variations in ovarian response to superovulation.