Avanços na criopreservação e subsequente cultivo in vitro de tecido ovariano e testicular de pequenos ruminantes

Rodrigues, Ana Paula RibeiroSilva, Bianca RégiaFerreira, Everton PimentelMbemya, GildasÑaupas, Lucy Vanessa Sulca

The in vitro culture of cryopreserved ovarian tissue (OT) and testicular tissue (TT) is one of the biggest challenges in reproductive medicine. This biotechnology aims to complete the in vitro development of primordial follicles and spermatogonia in the OT and TT, respectively, to obtain fertilizable oocytes and competent sperm for subsequent in vitro fertilization and the production of transferable embryos, with successful results only in mice. In goats and sheep, the cryopreservation of ovarian tissue (COT) and testicular tissue (CTT) with subsequent in vitro culture is still considered experimental. Although the success of COT in these species has already been demonstrated, it gives us hope for the use of this technology. Thus, in recent years, all our efforts have been focused on improving the culture system for vitrified OT with encouraging results regarding follicular development and survival, but there are no reports of successful production of competent oocytes, let alone healthy births. However, the cryopreservation and in vitro culture of TT from adult and pre-pubertal small ruminants are recent studies, and there are significant gaps in knowledge about the cellular and molecular consequences after thawing/warming and in vitro culture, although the results show a promising future.(AU)