Purpose: to develop an animal model for the study of, and training in, bovine biopsies. Methods: cow ovaries were obtained from a slaughterhouse and transported to the laboratory where the oocytes were aspirated, maturated and submitted to in vitro fertilization. On the 5th day after fertilization, the embryos were biopsied, with the zona pellucida being opened with a cutting blade fitted to the light microscope. One or two blastomeres were removed from the embryos and left in coculture for three additional days. After this time, embryo development was evaluated in comparison to a control group by morphological study and cell counts using specific staining for nuclei. Results: forty of the 57 biopsied embryos reached the blastocyst stage (70.2%) and hatching was observed in 11 (27.5%). Forty-two blastocysts were obtained in the control group (73.7%) and 11 of them hatched (26.2%). Cell counts showed no significant differences between groups. Conclusions: we conclude that the proposed protocol is technically feasible and supplies a good number of embryos because of the easy technique for obtaining bovine oocytes, thus representing a method that could be adopted for training.
Infertility; Cell culture; In vitro fertilization
