Estimation & Prediction

25 years of multibreed à¢â‚¬â€œ How a genetic evaluation has shaped the Australian Sheep Industry

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Abstract

The Australian sheep industry has historically had a strong culture of crossing within breed types as breeders target the best gene not the best breed. This helped bring about the release of the first multibreed sheep evaluation in 2000, to service the Terminal sheep breeds. Shortly after in 2005, Sheep Genetics (SG) was established to deliver national across-flock multibreed genetic evaluation systems to the Australian sheep industry for terminal, maternal and Merino sheep. Thus, providing a single national genetic evaluation "language" for Australian sheep breeders. Recent advancements in the Sheep Genetics evaluation have seen the release of the Combined LAMBPLAN genetic evaluation bringing together the Terminal and Maternal breeds. Enabled in part by the crossing of breeds across types as the self-replacing composites look to incorporate genes from terminal breeds to meet evolving breeding objectives. Throughout the lifetime of the national genetic evaluation the Australian sheep industry has transitioned from a wool centred industry to one focused on dual purpose lamb production systems. This has coincided with both an evolution to the breeding objectives but also the composition of the national flock. As the industry shifted, the genetic evaluation evolved with it. The growing importance of lamb meat drove the incorporation of carcass and eating quality traits into the system. These additions not only revealed an emerging decline in eating quality but also equipped breeders with the tools to reverse this trend. The decline in value of course wool has also seen the growth of shedding breeds and in turn their presence as a self-replacing maternal flock. This inadvertently triggered the research behind the combining of the Maternal and Terminal LAMBPLAN evaluations. This also came with changes to the underlying evaluation software OVIS to help better model the multi-breed nature through the pioneering implementation of meta-founder models. In both instances, the evaluation framework and its multibreed design have evolved to remain aligned with industry priorities. A history of continuous improvement in-step with the evolution of the breeding directions of industry has brought with it many challenges and will, in the future, bring forth many more. This paper examines how a new generation of multibreed genetic evaluations has been integrated into commercial systems to meet current industry demands and position the evaluation framework for future needs.

Keywords: 2026

How to Cite:

Bradley, P., Brown, D. & Walkom, S., (2026) “25 years of multibreed à¢â‚¬â€œ How a genetic evaluation has shaped the Australian Sheep Industry”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286088. doi: https://doi.org/10.31274/wcgalp.23850

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