Evaluación de la respuesta ovárica en cobayas (Cavia porcellus) superovuladas con la hormona folículo estimulante

Abstract

In the present study, the effect of superovulation with porcine follicle stimulating hormone (pFSH), at different times of cycle on the ovarian response of previously synchronized guinea pigs was determinated. 20 multiparous females were used, wich underwent a synchronization protocol with progesterone (P4) (Altrenogest; 0.22 mg/kg) orally for 15 days. Likewise, 3 groups were formed: group 1 (n=7), where a daily dose of 30 IU of pFSH was applied, divided into two applications, (morning and afternoon), on days 13, 14 and 15 (day of P4 withdrawal); group 2 (n=7), similar to the previous group, was administered the same dose of pFSH twice a day on days 15, 16 and 17; and group 3 (n=6) did not receive a dose, so it was considered as control. The following parameters were then evaluated: hours elapsed from the removal of P4 to the opening of the vaginal membrane (AMV-P4), hours elapsed from the application of pFSH to the opening of the membrane (AMV-pFSH), ovarian volume (VO), total follicles (FOLs), follicular diameter (D-FOLs), total corpora lutea (CLs) and diameter of CLs (D-CLs). As results, it was obtained that the application of pFSH before or after the synchronization with P4 did not influence the ovarian response and thus, morphological changes were observed in the ovary where the VO together with D-FOLs were higher for the pFSH groups; however, in relation to FOLs, CLs and D-CLs, they were not affected.