First successful cervical artificial insemination in the European roe deer (Capreolus capreolus)

The European roe deer ( Capreolus capreolus ) is unique among seasonal artiodactyls for undergoing embryonic diapause, a 4-5 months period of reduced embryonic development at the blastocyst stage. However, our knowledge of the reproductive physiology and endocrinology of the roe deer, particularly regarding embryo development and diapause, remains limited. Addressing this knowledge gap is crucial and necessitates further advancements in reproductive technologies. Here, this case report documents the first successful artificial insemination resulting in a pregnancy and live birth in this species, marking a significant breakthrough in its reproductive management. The timing of artificial insemination was assessed through careful behavioral observations of the time of mating by a vasectomized teaser buck. Cervical insemination was then executed with frozen-thawed sperm collected earlier from a fertile buck. DNA sequencing of the progeny, the parents and non-related individuals in the herd confirmed the parent-offspring relationship between the fawn and the sperm donor buck. While this study serves as a proof of concept, it also identifies potential areas for enhancement, such as improving estrus detection methods, sperm handling techniques, and the procedure of insemination itself. This research paves the way for advanced reproductive strategies in roe deer and potentially other species with similar reproductive characteristics.