Adición del líquido folicular como suplemento al medio de maduración in vitro de ovocitos de cobaya provenientes de ovarios de matadero

Abstract

In recent years, the in vitro maturation (IVM) process of guinea pig oocytes has been trying to improve. However, the results obtained until now are contradictory. Therefore, the present study sought to validate a protocol for obtaining follicular fluid (FL) from guinea pigs in estrus and then, to evaluate the effect of supplementing it in different percentages in a conventional medium in vitro maturation of guinea pig oocytes. For the first experiment, ten mestizo guinea pigs were used, which received a heat synchronization protocol based on oral progesterone for 15 consecutive days as a result 200µl of LF was obtained. In the second experiment, cumulus oocyte complexes (COC´s) were obtained from guinea pig ovaries using the slicing technique. The COC´s were distributed randomly in four IVM media containing different percentages of FL (T0= control, T1= 5%, T2= 10%, and T3 = 20%). After 24 hours, greater expansion of cumulus cells (CC) was observed in T1 (68.1 ± 3.01%) and T3 (66.6 ± 3.39%). It compared to T2 (54.35 ± 2 .72%) and T0 (43.19 ± 2.43%) with p<0.05, between groups. In addition, when evaluating the restart of meiosis progression, it was observed that the oocytes from T3 (33.46 ± 2.4%) and T2 (31.06% ± 1.93%) presented a higher percentage of oocytes in metaphase II, without a statistical difference between these two treatments; compared to the oocytes from T1 (24.52 ± 2.13%) and T0 (14.07 ± 1.72%). In brief, the supplementation of 10% guinea pig the follicular fluid in a conventional maturation medium resulted in a higher percentage of cumulus expansion, it improves the percentage of oocytes that reach metaphase II.