Canadian dairy cows among first in world bred to belch less methane

When Canadian dairy farmer Ben Loewith's calves are born next spring, they will be among the first in the world to bebred with a specificenvironmental goal: burping less methane.

In June,Loewith, a third-generation farmer in Lynden, Ont.,started artificially inseminating 107 cows and heifers with the first-to-market bull semen with a low-methane genetic trait.

"Selectively breeding for lower emissions, as long as we'renot sacrificing other traits, seems like an easy win," Loewithsaid.

The arrival of commercially available genetics to producedairy cattle that emit less methane could help reduce one of thebiggest sources of the potent greenhouse gas, scientists andcattle industry experts say.

Burps are the top source of methane emissions from cattle.

Semex, the genetics company that sold Loewith the semen, saidadoption of the low-methane trait could reducemethane emissionsfrom Canada's dairy herd by 1.5 per centannually, and up to 20-30 per centby 2050.

The company this spring began marketing semen with themethane trait in 80 countries. Early sales include a farm inBritain and dairies in the U.S. and Slovakia, said vice-presidentDrew Sloan.

If adopted widely, low-methane breeding could have a"profound impact" on cattle emissions globally, said FrankMitloehner, professor of animal science at University ofCalifornia Davis, who was not involved in developing thetrait.

Some dairy industry officials remain unconvinced aboutlow-methane breeding, saying it could lead to digestionproblems.

Canada's agriculture department said in an email that it hasnot yet assessed the methane evaluation system underlyingtheproduct but that reducing emissions from livestock was"extremely important."

Livestock account for 14.5 per cent of the world's greenhouse gasemissions. Methane is the second-biggest greenhousegas aftercarbon dioxide.

While farmers can feed additives to cattle to reduce methaneproduction, their effects wear off once cattle stop eatingthemand they are not approved for use in the U.S.,Mitloehner said.

The low-methane breeding material is the product of apartnership between Semex and Canada's milk-recording agencyLactanet and based on research by Canadian scientists.

In April, Lactanetreleased the world's first nationalgenomic methane evaluation, and has produced results fromHolstein cows and heifers on 6,000 farms, representing nearly60 per cent of Canada's dairy farms.

The registry drew on seven years of research by Universityof Guelph and University of Alberta scientists to measure themethane of dairy cattle.

The scientists captured the exhalations of cattle to measurethem for methane, and then compared the data againstgeneticinformation and milk samples.

Methane emissions from Canadian dairy cows vary widely, from250 to 750 grams per day, said Christine Baes, professor ofanimal biosciences at University of Guelph, who worked on theproject.

Selecting for the low methane trait could lock in lowerand lower emissions for successive generations, she said.

"The breakthrough here is linking these different componentsto have a national breeding value estimation for methane emissions based on real breath of animals," Baes said.

"We also have genomic information and we match those up andcreate almost a telephone book to say, 'this animal hasthesegenes and produces this much methane.'"

Semex is not initially charging extra for the methane trait,said Michael Lohuis, Semex's vice-president of research andinnovation. He declined to provide sales projections but expectssales to remain slow until financial incentives emerge.

The Canadian government currently offers no incentives forlow-methane cattle breeding, but the agriculture department saidin an email that Ottawa is working to introduce offset creditsfor reducing methane through better manuremanagement.

Some countries and food companies have begun to encouragefarmers to move to lower-emitting cattle.

New Zealand will begin taxing farmers for methane fromcattle in 2025.

Nestl and Burger King parent Restaurant BrandsInternational are tackling the methane problem in theirsupply chainsby changing what cattle eat.

Mitloehner said he expects companies to eventually recognizelow-methane breeding, too.

"Genetic change is permanent and cumulative across futuregenerations so it can add up to substantive reductions,"Lohuissaid. "This is certainly not the only tool dairy producers canuse to reduce methane on-farm, but itmay be the simplest andlowest-cost approach."

Other dairy experts said such an approach could beproblematic.

Juha Nousiainen, senior vice-president at Valio, a Finnishdairy, warned that breeding cattle to burp less methane couldcreate digestive problems.

Methane is produced by microbes in the cow's gut as itdigests fibre, not by the animal itself, he said.

Back on his farm, Loewith is eager to see how the breedingdecisions will play out.

"If it's something that you've doubled down on generationafter generation, then the impact becomes more significant."