Vitrification of equine in vivo-derived embryos after blastocoel aspiration

Abstract

Embryo cryopreservation is normally performed with great success in species like humans and cattle. The large size of in vivo-derived equine embryos and the presence of a capsule—impermeable to cryoprotectants—have complicated the use of embryo cryopreservation in equine reproduction. A breakthrough for this technique was obtained when large equine embryos could be successfully cryopreserved after collapsing the blastocoel cavity using a micromanipulation system. High pregnancy rates have been obtained when vitrification is used in combination with embryo collapse.