Cows belch methane. Now researchers are trying to breed them to burp less

Cows emit methane. It's long been debated which end it comes out and Christine Baes doesn't think it's the farts.

"It is indeed the burps that cause the methane, or most of the methane," said Baes, an associate professor in animal bioscience at the University of Guelph.

Baes has been measuring those burps as part of an international research project using genetics to try and figure out how to breed cows who eat more efficiently and produce less methane. The agriculture industry is trying to cut down its emissions — and cow burps play a big part.

Dairy production has "a bad rap for being environmentally unfriendly," said Baes. "Every industry is of course responsible for reducing their impact on the environment as much as possible."

The research, known as the Efficient Dairy Genome Project, has a two-fold purpose. Cows that produce less methane will have less environmental impact, while cows needing less feed will save farmers money. Feed is one of the most expensive parts of running a dairy farm.

Baes and her team are measuring and collecting data on hundreds of different cows at a research barn near Elora, Ont., north of Guelph.

They study how much cows eat, how much milk they produce and what's in that milk, among other traits.

They measure cow burps four times a day using a small green machine which captures methane amounts. The machine wheels up to the cows, who stick their face in and get a few pellets of food while it records their burps. Unlike human burps, cow burps aren't really audible, so it's hard to tell when they are emitting methane.

The data lets the team weed out cows that are "efficient" and those who aren't.

"We can correlate the amount of methane that they produce with their DNA," she said. "We can actually select animals that have the right DNA that don't produce much methane and that more efficiently use their feed."

Studying cows in multiple countries

Mary De Pauw is managing the entire project from the University of Alberta in Edmonton. A team there is measuring the same cow traits and combining it with the findings in Guelph, as well as with researchers in five different countries.

De Pauw said sharing the data has made the research much stronger and more reliable.

"We definitely need to reduce the environmental impact of agriculture production and I think it is a very attainable goal," she said. "I think we have a very good chance of taking the tools that we produce in this project and getting it out into the industry."

'Very, very long term thing'

The Food and Agriculture Organization of the United Nations said livestock makes up 14.5 per cent of all human-caused greenhouse gas emissions, with cattle being the dominant producers of methane.

Baes figures the average cow emits between 80 and 120 kilos of methane per year.

"You're talking about a very large amount of methane being produced," she said. "Even if we can have a point one per cent change in the first year after applying a breeding program ... it would be a very small part of a much larger program."

She understands this will take time, calling it a "very, very long-term thing." The project is slated to take four or five years — researchers are about halfway through now and there could be an extension. She doesn't expect to roll out findings for another two or three years.

But the work is particularly meaningful to Baes, given she grew up around cows on a dairy farm.

"I'm a little bit in love," she admits. "Over time I think it really will make a difference to breed cows that are less environmentally unfriendly."