Pig embryo production by in vitro maturation and fertilization of ovarian oocytes. A review

Abstract

In addition to their major role in food production, pigs have become an increasingly important species in biomedical applications involving the production of pharmaceutical products and as donors of organs for xenotransplantation. They are also used as a model for studies of human diseases. In pigs, as in other mammals, immature oocytes released from ovarian follicles resume meiosis and complete maturation in culture. Although several systems have been established to generate embryos in vitro, the quality of embryos produced in vitro is inferior to those produced in vivo. This review focuses on recent achievements in the development and identification of defined conditions for the in vitro production of porcine embryos. It also discusses the effects of oocyte-donor age, size of follicles used for oocyte recovery, synchronization of meiosis before IVM, supplementations of media for IVM, IVF and embryo culture, oxygen tension during culture and the ways for overcoming polyspermy.