Banca de DEFESA: PAULO CASTELO BRANCO DE GOUVEIA FILHO

Use of eCG prior to OPU with follicular wave sychronization for in vitro embryo production in Murrah buffaloes and Nellore females

 Follicular growth, OPU, Bovine, Buffalo, Oocyte, Embryo IVP

This study aimed to evaluate the effect of stimulation with equine chorionic gonadotropin (eCG) prior to oocyte collection (OPU) on the number of aspirated follicles, number and quality of recovered oocytes, fertilization rate and early embryo development in vitro in Murrah buffaloes and Nellore females. Sixteen sessions of OPU (in a Latin square scheme) were performed in Murrah buffaloes and 10 sessions in Nellore females to evaluate the effect of a 300IU dose of eCG. The wave of ovarian follicular development was synchronized, and three days later, eCG was administered (300IU). OPU was performed on day 6, and viable oocytes were used for IVM and IVF. After in vitro fertilization, the rates of fertilization and cleavage, and the number of cells in 48 h were evaluated. In buffaloes, the use of eCG resulted in a worsening of the results obtained in comparison with the control group, with a difference in the number of follicles, total oocytes recovered, rate of oocytes recovered, and in the rate of embryos produced (P< 0.05), however the oocyte retrieval rate was better in the group treated with eCG, (P<0.001)., while in Nellore females, after in vitro fertilization, the fertilization and cleavage rates and the number of cells in 48 h were evaluated. There was no difference in the number of follicles, number of oocytes and morphological quality of oocytes between treatments (P>0.05). The oocyte retrieval rate was better in the eCG-treated group, (P<0.001). The variables, viable oocyte rate, cleavage rate, and embryo rate did not differ (P>0.05). In conclusion, the synchronization of follicular wave emergence associated with ovarian stimulation with a dose of 300 IU of eCG was not effective in increasing the quantity and quality of viable oocytes in ultrasound-guided transvaginal follicular aspiration, not resulting in improvement in the production of oocytes. in vitro embryos in both species.