Towards Improving the Outcomes of Assisted Reproductive Technologies of Cattle and Sheep, with Particular Focus on Recipient Management

SIMPLE SUMMARY: The Australian livestock industry has grown significantly over the last decade. In order to meet national consumer demands, as well as the growing export market, more efficient means of producing lamb and beef products are required. Assisted reproductive technologies (ARTs) can be used to increase genetic gain and improve overall herd reproductive potential. This review focuses particularly on the management and selection of recipient animals utilised in ARTs. The condition and quality of the recipient animal is pivotal to the efficiency of reproductive technologies, as the inability of an embryo to establish and maintain pregnancy is the most significant cause of reproductive losses. A variety of external, uncontrollable factors affect the reproductive potential of an individual within any given reproductive season, limiting reproductive efficiency. Therefore, improved selection and management of recipient animals can help to increase the productivity of the Australian livestock industries. ABSTRACT: The Australian agricultural industry contributes AUD 47 billion to the Australian economy, and Australia is the world’s largest exporter of sheep meat and the third largest for beef. Within Australia, sheep meat consumption continues to rise, with beef consumption being amongst the highest in the world; therefore, efficient strategies to increase herd/flock size are integral to the success of these industries. Reproductive management is crucial to increasing the efficiency of Australian breeding programs. The use of assisted reproductive technologies (ARTs) has the potential to increase efficiency significantly. The implementation of multiple ovulation and embryo transfer (MOET) and juvenile in vitro fertilization and embryo transfer (JIVET) in combination with genomic selection and natural mating and AI is the most efficient way to increase genetic gain, and thus increase reproductive efficiency within the Australian livestock industries. However, ARTs are costly, and high variation, particularly between embryo transfer recipients in their ability to maintain pregnancy, is a significant constraint to the widespread commercial adoption of ARTs. The use of a phenotypic marker for the selection of recipients, as well as the better management of recipient animals, may be an efficient and cost-effective means to increase the productivity of the Australian livestock industry.