Dairy farmers are benefiting in herd improvement thanks to vital genetic research, writes Rebecca Connell.
In 2019 the global dairy industry valued at USD$673.8 billion, and is projected to increase by a further USD$400 billion by 2024. Australian dairy farmers represent a significant proportion of this industry. Australian diary is the twelfth highest producer of cow milk in the world, worth $13 billion, with over 5,500 famers and 43,000 employees nationwide.
17 percent of global greenhouse emissions is methane gas produced by livestock, with dairy cattle accounting for 20 percent of this. In the age of climate change there is a growing need to adapt to these challenges.
“There are two sides to this issue: We need to reduce the dairy industry component of agriculture that contributes to global warming, reducing the methane that comes from cows, while also making sure cows can still produce milk in a warming world.” says Professor Jennie Pryce, Principal Research Scientist of Agriculture Victoria and La Trobe University, AgriBio.
“This problem can be addressed through selectively breeding advantageous traits into our livestock. As cows have become more productive the emissions per litre of milk produced is reduced. The industry can also breed for characteristics such as heat tolerance.”
Selective breeding has been an important component of agriculture since the 1700’s. In 2020, animal geneticists are looking for the genomic markers which are associated with cow productivity, health, their reproductive efficiency, heat tolerance, and reduced methane emissions in order to improve the selective breeding process.
As the animal program leader of the DairyBio Animal program, which is funded by Dairy Australia, Agriculture Victoria, and the Gardiner Foundation, Pryce and her fellow researchers are working to understand the cow genome. Such research has developed heat tolerance breeding values using genomic technologies which are now used in cow breeding on a national scale.
“Farmers make breeding decisions using multiple breeding values available through DataGene, the organization leading herd improvement in Australia, with the innovation coming from the DairyBio team,” says Pryce. “Thanks to our research, Australia is the first place in the world to release feed efficiency and heat tolerance values in breeding selection. Other research groups worldwide are now doing the same thing. We are leading the way.”
This year alone, Pryce has collaborated with geneticists in over eight countries, including USA, Canada, New Zealand, and Belgium, and produced more than 20 research papers.
One recent study involved the collaborative effort between Agriculture Victoria Research and La Trobe University, The Universities of Florida and Wisconsin, and the Federal University of Uberlândia, Brazil. Data was gathered from over two thousand Jersey cows, looking at sire conception rates, bull semen fertility values, and bull genomic data. The resulting paper reinforces genetics in selective breeding for fertility in dairy bulls, an overlooked aspect to breeding compared to female fertility.
“Partnerships with other countries is crucial to these studies as we can gather more data and have more accurate results,” says Pryce. “The contribution of cattle to the problem of global warming is a problem that affects us all, and it takes a global effort to address these big problems.”