WELLINGTON COUNTY – On June 6, the University of Guelph (U of G) announced cows will be bred to burp less with groundbreaking methods based on its research.
Globally, nearly 14 per cent of all human-caused greenhouse gas emissions (GHGs) come from burping livestock, experts say.
And methane, also known as CH4, has 32 times more global warming impact than carbon dioxide (CO2).
Dr. Christine Baes is the chair of the Department of Animal Biosciences at the University of Guelph’s Ontario Agricultural College and team lead on the project.
She told the Advertiser burping dairy cows are likely responsible for 2% of the greenhouse gases in Canada.
“When you think about the dairy industry, it’s not as bad as people say it is. But even so, we can still do something about that, because there’s a lot of variation between individual animals,” said Baes.
Genetic evaluation
Researchers along with Baes have developed a new method as part of the Resilient Dairy Genome Project (RDGP). The method is being used to establish roughly how much methane will be produced by each of the approximately 700,000 registered dairy cows across Canadian farms.
Being the first national genetic evaluation in the world to help select low-methane dairy cows, it is expected to help reduce GHGs on farms without causing harm to milk production.
This means breeders are now able to predict which cows will produce offspring that will burp less methane into the air when they are fully grown — even as they continue to produce as much or more milk.
Canada has an LPI (Lifetime Performance Index) of 67 different traits farmers can choose from when picking cattle. The traits include how much milk, protein and fat the cow produces, if they are healthy, fertile, etc. All the traits are put together and then animals that rank the best are selected.
“Now we have 68 traits, and methane can be included in that selection process,” Baes began.
“They can now not only be selected on how much methane they produce, but this new trait can be included in the index that we use to choose [animals].
“In April of this year, Canada became the first country in the world to officially select for methane emissions.”
Although methane efficiency was available in April, officials said it likely won’t be included into the LPI index until sometime in 2024.
Baes and other researchers have been working at the Ontario Dairy Research Centre in Elora. There have also been investigators working in dairy research facilities in Alberta, as well as Australia, Denmark, Spain, Switzerland, and the U.S.
The Canadian researchers have used MIRS (mid-infrared spectroscopy) to measure the absorption of infrared light in milk samples from nearly 200 dairy cows. The technology measures a handful of milk components such as fats and proteins.
Complicated stomachs
“We’re starting to look at how we can combine the nutrition and the genetics of animals,” Baes said.
She added diet can also impact how much methane each cow is producing.
“If you have a cow in a very arid environment who’s just eating really poor-quality grass, the microbes in her stomach are going to be a lot different than the ones who are being fed really high-quality forages, like here in Canada,” she said.
Baes also wants to begin looking at the interaction between nutrition and genetics in dairy cows moving forward.
She estimates around 30% of variation can be controlled with genetics. The other 70% is based on factors such as the environment.
Dr. Michael Lohuis is the vice president of research and innovation at Semex, a cattle breeding organization owned by WestGen, EastGen and CIAQ.
Semex is a world leader in developing new techniques for embryo transfer, and is one of the only genetic companies with a fully integrated embryology laboratory with a focus on embryo freezing, in-vitro fertilization and genomics.
Lohuis told the Advertiser cows have more complicated stomachs than humans, pigs or chickens, which partly explains why they produce more methane. They have a four-chambered stomach, a large part of which is called the rumen.
“Inside the rumen, there is a whole bunch of microbes, including bacteria and organisms that are even older than bacteria like archaea,” Lohuis said.
Those microbes mean cows can digest foods that humans cannot.
Lohuis added these types of foods are usually corn, hay or other plant materials. He said cows and sheep evolved to have a rumen in order to digest the roughage in their diet.
There is a symbiosis that exists in the rumen and the microbes have a warm and moist environment to get access to the cow’s feed and, with special enzymes, break down the cellulose. Sugars and starches are then released, which the cow absorbs.
In the breaking down of the cellulose, Lohuis said hydrogen is released. If there is too much hydrogen it can become toxic, so the cow needs a way to get rid of it – they achieve this by burping out methane.
“That methane, 95% of it comes out of the mouth and you never hear cows burping. Not like humans,” said Lohuis.
Cattle reproduction
Lohuis said that there can now be selection pressure on methane efficiency and this new trait, designed by Lactanet, is meant to be neutral for production, which means that there is no significant correlation with other traits.
Currently the methane trait is only being used for dairy cattle – more specifically Holsteins, which Lohuis said make up about 95% of the dairy population in Canada.
Once more data is collected, through research like that conducted by Baes, the trait will be extended to other breeds such as Ayrshire and Jersey cows, the two next breeds of significance.
“People that are concerned about climate change, I think welcomed this approach that you can start breeding cattle to emit less methane,” said Lohuis.
He said doing this with breeding will take time.
“It only reduces methane by about 1.5% per year,” he said. “One good thing about breeding is it accumulates generation after generation. If you a make 1.5% change this year, the next generation adds on to that.”
Baes added the reaction from the public to her research and the new trait for dairy cows has been positive.
“When we breed for methane reduction, we’re actually breeding for more efficient cows,” she said. “And what that means is when they take a bite of food, they can use that food to make milk as opposed to burping it out.
“We’re not doing anything other than selecting healthy animals that can more efficiently produced milk, which is really a super win-win for everybody.”
