Recent advances in superovulation in sheep / Recentes avanços na superovulação de ovelhas

ABSTRACT

Nearly three years ago our research team published a review of intrinsic determinants and predictors of superovulatory responses in ewes (18th International Congress on Animal Reproduction, Tours, France; 26-30 June 2016; Theriogenology 2016;86130-143). Heres a summary of major advances in superovulatory treatments of ewes reported over the last three years and of some most anticipated future directions. The rate of genetic improvement within a synthetic population of animals is significantly enhanced by an application of superovulation and embryo transfer. However, the sheep industry has progressed rather slowly in terms of implementing these technologies in comparison to other species although sheep have been used in many studies that paved the way to the development of modern assisted reproductive technologies (ARTs). Recently, several improvements in determining ovarian responses and non-invasively collecting/transferring embryos have been reported but some most frustrating problems associated with hormonal ovarian superstimulation (e.g., unpredictable and highly variable individual responses) remain unresolved. This warrants continued studies of both the physiological basis of and novel approaches to superovulatory treatments in sheep.(AU)