Ovarian function in domestic ruminants: Mechanistic and translational aspects

Abstract

The purpose of this review is to illustrate the critical value of integration of both in vitro and whole animal approaches in order to make real progress in terms of understanding the underlying mechanisms controlling ovarian follicle development and also in utilising domestic ruminants as models for the human in the translational development of interventions to address infertility. In terms of mechanistic aspects, this review concentrates on interactions between members of the TGFβ super family derived from both somatic cells (AMH) and the oocyte (BMP6, BMP15, GDF9) and illustrates how integration of in vitro and in vivo approaches has allowed us to propose a functional relationship between these factors in regulating the progression of follicles through the gonadotrophin-responsive to dependent phases of follicle development. In this section, a new in situ direct ovarian perfusion system is introduced.. In terms of translational aspects, this review details the integration of in vitro and in vivo approaches in order to develop methods in sheep that allow high rates of restoration of ovarian function and fertility following whole ovarian cryopreservation and autotransplantation in adult animals. This methodology should be of value to women at risk of premature ovarian failure. It is concluded that, given the vastly increased cost of ruminant research in developed countries, that meetings such as the RRS can play a critical role in encouraging international collaboration in order to ensure the continued exploitation of monovulatory ruminants as valuable experimental models.