'Beef-on-dairy': harnessing assisted reproductive technologies to improve performance and sustainability in...

'Beef-on-dairy' describes the strategic use of beef semen on dairy females that are not required to produce replacement heifers. Adoption of beef-on-dairy systems has increased rapidly in recent years, enabled by the growth in use of sex-sorted semen to generate replacement females. This shift presents both opportunities and challenges: the rate of genetic gain can be accelerated, but the supply of high genetic merit male dairy calves will need to be generated through alternative means, and there will be an increased requirement for beef sires specifically suited for mating with dairy females. Assisted reproductive technologies, including sex-sorted semen and embryo-based approaches, offer considerable potential to enhance the genetic merit of both dairy and beef sires. When applied strategically, these technologies can accelerate genetic progress in dairy herds and improve the beef value of surplus calves born. The implementation of these technologies is challenging in seasonal-calving systems, however, and use of sex-sorted semen and embryo technologies must be carefully managed. In addition, the availability of suitable donor and recipient animals for embryo production and transfer is inherently seasonal, creating logistical constraints. Despite these challenges, more effective integration of dairy and beef breeding strategies offers substantial benefits. These include improved biological and economic efficiency of pasture-based milk and beef production, reductions in waste and animal welfare concerns, and the delivery of higher-value beef products. Ultimately, the strategic alignment of dairy and beef breeding decisions represents a key opportunity to enhance the sustainability, resilience and societal value of modern livestock production systems.