Professor Julius van der Werf
Holds a PhD from Wageningen University and also studied at Cornell University in New York, was Assistant Professor in Wageningen from 1985 to 1993 and Senior Researcher at the National Institute for Animal Science and Health between 1993 and 1997.… In 1997, he moved to Armidale, where he is now Professor in Animal Breeding and Genetics at the University of New England.
He specialises in research into genetic evaluation, breeding program design, breeding objectives and genomic selection. He supervised more than 65 PhD students, and he managed the Sheep CRC genetics program from 2003-2019 during which genomic selection was introduced to the Australian sheep industry. He has led many large industry funded projects in sheep, including the MLA resource flock project, the Merino link genotyping project and the MLA/MDC project on selecting for more methane efficient sheep. He has been a member of several industry advisor committees and was in the panel of experts of the Australian Research Council. He was editor of leading journals in animal breeding such as GSE and JABG. He was Head of School of Environmental and Rural Science at UNE from 2021-2023 and is now convenor of the Animal Science group. In 2021 he was awarded the Helen Newton Turner medal for in recognition of “Outstanding contributions to Australian Animal Genetics”
Developing sustainable animal breeding programs for genetic improvement
Introduction The role of animal production must be reconsidered in a world facing major challenges, including a growing human population, increasing demand for animal protein, and the impacts of climate change. Animal production systems must use valuable resources such as land and water efficiently, avoid competing with human food sources, and operate within ethical and environmental boundaries.… Animal protein production spans a range of systems, from intensive operations such as poultry and pig production to extensive systems such as beef cattle and small ruminants. Pig and poultry production are efficient systems for converting feed into animal protein, and several decades of focused genetic improvement have contributed to substantial gains in that efficiency. Extensive ruminant systems convert feed that is indigestible for humans, often sourced from land unsuitable for crop production. Genetic improvement has generally had less impact on these systems — dairy being a notable exception — as they tend to be low-input systems on marginal lands, driven in many parts of the world by smallholders. Both systems are under scrutiny. Pig and poultry systems face disease challenges and welfare concerns from an increasingly urban consumer base, whereas ruminant systems face pressure to reduce their environmental impact, particularly through lower methane emissions. This paper explores the potential role of genetic improvement in advancing sustainable animal production systems.
Materials Sustainable breeding programs are built around clearly defined goals that support sustainable production systems, affordable genetic improvement strategies, and the long-term maintenance of genetic variation. The latter becomes increasingly important as breeding programs become more effective, since a relatively small number of parents may be used to produce a large next generation. Under increasingly variable climate conditions, genetic diversity is also essential for maintaining population resilience to changing environments, as further discussed at this conference by [1]. Successful genetic improvement depends on well-defined breeding objectives, effective investment in trait measurement, an efficient genetic evaluation system, and a clear understanding of breeding program structure — from nucleus improvement to dissemination across the wider population.
Results Well-designed breeding programs can achieve sustainable genetic improvement in livestock, with productivity increases of 1–2% per annum. For example, milk production per cow has more than doubled in many countries since the introduction of artificial insemination (AI) in the 1950s. In the United States, production per cow per lactation increased by 72% between 1985 and 2015, of which approximately 70% was attributed to genetic selection [2]. Similarly, broiler growth rate increased by approximately 400% between 1957 and 2005 [3], with 80–90% of this attributed to genetic selection. Rates of genetic gain have increased further over the past decade with the introduction of genomic selection [4], particularly in dairy cattle, though this will only be beneficial within programs that already have clear breeding objectives and adequate genetic evaluation.
Discussion Many ruminant breeding programs now focus on reducing enteric methane emissions. Bioeconomic modelling shows that selecting for lower methane per animal is likely to reduce productivity and increase methane intensity — the methane produced per unit of product. An optimal strategy therefore focuses on increasing production efficiency while limiting the correlated increase in methane, not unlike selection for improved feed efficiency. Genetic improvement for productivity alone can contribute substantially to reducing methane intensity, particularly where scope for improvement is greatest, as in many developing countries. However, despite considerable effort, rates of genetic gain have been disappointing for ruminants in extensive systems. Given their major role in global food production, renewed investment in resolving this seems well justified.
Conclusion Many ruminant breeding programs now focus on reducing enteric methane emissions. Bioeconomic modelling shows that selecting for lower methane per animal is likely to reduce productivity and increase methane intensity — the methane produced per unit of product. An optimal strategy therefore focuses on increasing production efficiency while limiting the correlated increase in methane, not unlike selection for improved feed efficiency. Genetic improvement for productivity alone can contribute substantially to reducing methane intensity, particularly where scope for improvement is greatest, as in many developing countries. However, despite considerable effort, rates of genetic gain have been disappointing for ruminants in extensive systems. Given their major role in global food production, renewed investment in resolving this seems well justified.