Burping bovine: University of Guelph researchers develop tool to predict how much methane a cow will belch out

University of Guelph (U of G) researchers have been looking at ways to breed dairy cows that burp out less methane, a harmful greenhouse gas emission contributing to climate change.

“Methane has a global warming potential 28 times that of carbon dioxide,” said Christine Baes, chair of the U of G animal bioscience department.

Baes is leading a team from the university and Ontario Dairy Research Centre that has developed a new tool, which estimates how much methane will be produced by each of the roughly 700,000 registered dairy cows on farms across Canada.

Researchers with the University of Guelph are working to breed low-methane producing cows. (Spencer Turcotte/CTV News)

Almost 14 per cent our greenhouse gas emissions around the world come from burping livestock, according to the U of G. The university is hoping to change that.

“Over the past several years, our team has been trying to deliver a genetic evolution for methane emission and feed efficiency in dairy cattle,” Baes said.

It means breeders can now select which cows will produce calves that, when fully grown, will belch out less greenhouse gas.

“We're really proud that this research has resulted in Canada being the first country worldwide to be able to deliver genetic evolutions for methane emissions,” Baes said.

HERE’S HOW IT WORKS

At the research centre, which operates in partnership with the university, cows put their heads into 'green feed machines’ and as they eat their hearty meal, paired with heavy breathing and burping, they produce data.

“So when the animal is breathing, those gases are taken up by the machine and measured,” Baes explained.

With about 500 cows at the research centre, there is no shortage of burps to measure.

In fall 2022, the team published a paper in the Journal of Dairy Science describing how to predict methane emissions in dairy cattle using milk mid-infrared reflectance spectroscopy (MIRS).

The U of G said in a recent study that MIRS data could be used to predict methane emissions. Matching up milk samples with DNA samples from individual cows allows a farmer to pinpoint which animals to breed for lower emissions. Ultimately, the hope is that it will contribute to more sustainable dairy operations.

WHICH END IS WORSE?

When it comes to passing gas from the back passage, Baes said the main concern comes from the mouth.

“Many people do think the problematic gas comes out the back end but that's not the case. About 95 per cent of enteric methane emissions are coming out of the front end of the animal,” she said.

The new methane emissions evaluations will initially be provided to owners of Holstein cattle involved in registration and herd testing. They make up the majority of Canada's dairy herd.

Other breeds will be included as more data is collected.