Culture systems for bovine embryos

In vitro production of livestock embryos is important for both agriculture and biomedical research. In spite advances in designing media and culture systems, we do not yet know precisely what the embryo needs. It is known that origin of the oocyte affects the blastocyst rate, and that post-fertilization culture conditions influence the quality and viability of these blastocysts. However, the effects of in vitro culture systems on pre-implantation as well as post-implantation development have not been well characterized. The use of advanced molecular biology tools to produce functional blue-prints of in vitro-produced embryos has revealed that the optimum culture conditions for preserving developmental potential remains elusive. This review provides an overview of media design and culture systems, as well as their short and long-term effects on cattle development with an emphasis on disruption of embryonic gene expression.