The livestock industry, particularly cattle farming, significantly contributes to global greenhouse gas emissions. Cows account for approximately 62% of the agricultural sector's contribution to these emissions, a substantial portion of the 12% total attributed to agriculture by the UN's Food and Agriculture Organization. Addressing this requires innovative approaches to mitigate methane emissions, a potent greenhouse gas produced by bovine digestion. While reducing meat consumption and adopting plant-based alternatives are important strategies, advancements in animal genetics offer a compelling alternative.
Researchers at the University of Alberta, led by beef cattle geneticist John Basarab, have been pioneering a method to breed cattle with significantly reduced methane emissions. Their work, presented at Farmfair International in November, focuses on identifying and utilising genetic markers associated with lower methane production. Currently, most farmers prioritise traits like lifespan and milk yield when selecting breeding stock, often overlooking the environmental impact of methane. However, as Basarab explains, methane production represents a significant inefficiency: "About two to 12 per cent of the energy an animal consumes is lost as methane. Thatâs an inefficiency that costs money."
To identify low-methane-producing cows, Basarab's team employs a sophisticated system akin to a "bovine breathalyser." This apparatus measures methane levels in the cow's breath and burps â the primary route of methane expulsion â while simultaneously collecting genetic samples. Analysing thousands of cows in this manner allows researchers to correlate specific genetic sequences with lower methane output. The project, involving approximately 2,000 Canadian cows, utilises a five-year research programme. While the current method involves a substantial investment (£140,000 per machine, approximately), requiring around a month of readings for accurate analysis, the team is exploring cost-effective alternatives such as infrared imaging of cow manure.
However, breeding for low methane production alone presents challenges. Reducing methane output could potentially impact other desirable traits such as growth rate or temperament. Therefore, Basarab's team aims to integrate methane data with a genetic index encompassing 17 other crucial traits, creating a holistic score for farmers to use in their breeding decisions. This comprehensive approach ensures that environmental benefits are not achieved at the expense of economic viability.
Currently, genetic testing costs around £40 per cow, a barrier for many farmers. To encourage wider adoption, the team is exploring carbon offset schemes and financial incentives to make genetic screening more accessible. While complete methane elimination in cattle is unlikely due to the complexity of the genetic factors involved, Basarab estimates that widespread genetic selection for low methane could reduce beef cattle emissions intensity by approximately 30%. This, coupled with other mitigation strategies such as dietary adjustments and carbon sequestration through grassland management, could potentially bring the Canadian cattle sector closer to net-zero emissions.
Jeff Nonay of Lakeside Dairy in Sturgeon County highlights the practical implications of this research, particularly for dairy farmers. He points out that the ability to select cows with equal productivity but lower methane emissions allows for environmental sustainability without compromising herd size. This demonstrates the potential for significant progress in achieving environmental goals within the agricultural sector through a combination of scientific innovation and responsible farming practices. The adoption of genetic indexes is already gaining traction amongst farmers, showcasing the potential for widespread impact.
