CALGARY -- As Canada doubles down on efforts to reduce harmful methane emissions, experts say one of the trickiest hurdles standing in the way is the burping cow.

Methane -- a clear, odourless gas -- accounts for just 13 per cent of Canada's total greenhouse gas emissions, but because it is better than carbon dioxide at trapping heat it is believed to be responsible for at least one-third of global warming recorded to date.

That makes it a high priority for governments seeking to live up to their climate change commitments. Earlier this month, Canada confirmed its support for the Global Methane Pledge, which aims to reduce global emissions by 30 per cent below 2020 levels by 2030. The initiative, led by the U.S. and Europe, will be launched at the UN climate summit in Scotland in November.

Forty-three per cent of Canada's total methane emissions come from the oil and gas industry, and the federal government has already put regulations in place to reduce methane emissions from the oil and gas industry by 40 to 45 per cent over 2012 levels by 2025. Last week, Canada said its new goal will be to align with the International Energy Agency's recommendation that methane from the oil and gas industry must be cut 75 per cent from 2012 levels by the end of this decade.

But when it comes to agriculture, there are no regulations, or even federal targets, in place. This is in spite of the fact that the industry is responsible for 24 per cent of Canada's total methane emissions.

Methane is a natural byproduct of cattle digestion, meaning it is emitted into the atmosphere every time a beef or dairy cow burps or passes gas. And unlike in oil and gas -- where existing leak detection and repair technology can go a long way toward reducing methane emissions -- there is no obvious solution for the problem yet.

"I think the biology's a bit more complicated on the agricultural side than it is on the oil and gas side," said Tim McAllister, a Lethbridge, Alta.-based research scientist with Agriculture and Agri-Food Canada. "A lot of the oil and gas issues I think can be handled by engineering solutions."

That doesn't mean scientists aren't trying. Around the globe, research is being done on everything from optimization of cattle diets to the addition of feed additives -- everything from nitrates to seaweed -- in an effort to reduce methane emissions.

Scientists are also looking into the possibility of a vaccine that could target the methane-producing microbes in a cow's gut. Some researchers are even experimenting with putting mask-like accessories over a cow's mouth to trap methane burps.

Between 1981 and 2011, the beef industry was able to reduce its total greenhouse gas emissions intensity by 15 per cent, said Brenna Grant, manager of Canfax Research Services, the research arm of industry group The Canadian Cattlemen's Association. Those improvements were largely due to improvements in feed quality and efficiency.

Grant said last year, the beef industry set its own target of reducing primary production greenhouse gas emissions intensity by 33 per cent over the next 10 years -- a goal she acknowledged is ambitious.

"Let's just say it's going to be a stretch. And the thing is, we wanted to make it a stretch," she said. "We wanted it to be something we would really have to strive and work on."

Experts say even if a technology makes sense scientifically, it also has to make economic sense. No farmer is going to pay for a methane-reducing feed additive unless it somehow also improves his or her bottom line.

Guillaume Lhermie, director of the Simpson Centre for Agricultural Policy and Public Education at the University of Calgary, said so far, farmers have remained relatively unaffected by Canada's current climate policies. The use of on-farm fuels, for example, remains exempt from federal carbon pricing.

But Lhermie said the beef industry should expect to come under increasing regulatory and governmental pressure in years to come. He added that in order to avoid onerous emissions-related legislation and maintain greater freedom in production decisions, the sector needs to proactively tackle the issue.

"It is almost certain that there will be increasing pressure to reduce emissions from the agricultural sector," he said. "It could mean massive disruption for the sector."