In vitro production of (farm) animal embryos

Abstract

Over the past decades, in vitro production (IVP) of bovine embryos has been significantly improved, and in particular bovine IVP is now widely applied under field conditions. This in vitro technique provides new opportunities for cattle producers, particularly in the dairy industry, to overcome infertility and to increase dissemination of animals with high genetic merit. Improvements in OPU/IVP resulted in large-scale international commercialization. More than half a million IVP embryos are generated on the yearly basis demonstrating the enormous potential of this technology. These advances and the fact that bovine and human early development is remarkably similar have prompted the use of bovine embryos as a model system to study early mammalian embryogenesis including humans. In horses, OPU/IVP is also an established procedure for breeding infertile and sports mares throughout the year. It requires ICSI because conventional IVF does not work in this species. In small ruminants, application of IVP on the commercial and research basis is low compared to other livestock species. Despite all the improvements, embryos generated in vitro still differ from their in vivo-derived counterparts. Embryos must adjust to multiple microenvironments at preimplantation stages. Consequently, maintaining or mimicking the in vivo situation in vitro will aid to improving the quality and developmental competence of the resulting embryo. The successful clinical application of the techniques in reproductive biotechnology requires both species-specific clinical skills and extensive laboratory experience.