How Now Green Cow
How Now Green Cow is examining how farms and food are shaping and being shaped by the climate crisis. Got a food and climate question? Send it to [email protected] so it can be addressed in a future story.
In humans, what goes in your gut affects what comes out; just ask your butt after you’ve had a load of baked beans.
It’s the same for cows, who produce copious amounts of methane in their multi-chambered stomachs (specifically in the rumen). Farmers and scientists across Canada are now looking for new ways to improve a cow’s diet to reduce the amount of heat-trapping gas they belch out.
Animal agriculture accounts for about 12 per cent of global greenhouse gas emissions, said Cameron Olson, a farm animal technical consultant with Elanco Canada who researches feed additives, in an email interview. Canada’s beef cows tend to be more efficient than the global average, accounting for about 4.2 per cent of this nation’s carbon emissions.
“Part of the reason that Canadian beef is more GHG-efficient than the global average is due to the feed additives available in Canada for producers to leverage,” he said, many of which have been in use for years.
Olson said most of these additives reduce emissions by improving animal health and lowering the amount of raw materials needed to feed them. Some specifically address methane, with some estimates saying about 85 per cent of Canadian beef cows are fed a methane-reducing additive at some point in their life.
One of the more common methane-reducing additives on the market now was monensin, said Barry Robinson, a beef and dairy nutritionist who works with Sturgeon County farms such as Lakeside Dairy. By interacting with the billions of bacteria and yeasts in the rumen, this additive can reduce the amount of feed needed to raise a feedlot cow by about five per cent.
“If you’re feeding less feed, there’s a lower carbon footprint,” Robinson said.
High-tech grub
Tim McAllister has for many years studied ways to reduce methane from cows at Agriculture and Agri-Food Canada’s Lethbridge Research and Development Centre, some of which involve feed additives.
Cows lose up to 10 per cent of the energy they take in as methane which they burp and breathe out, McAllister said. Those losses are caused by microscopic methane-making creatures called methanogens that hang out in a cow’s rumen. Reduce those emissions, and you reduce your energy losses and get more beef and milk per cow.
One rising star in the feed additive world is a white powder called 3-nitrooxypropanol, or 3-NOP (“three N-O-P”). McAllister said this compound reduces methane emissions by blocking specific enzymes used by the methanogens in a cow’s stomach. A 2020 Penn State study found 3-NOP could cut methane emissions from dairy cows by about 25 per cent while slightly boosting their milk output.
3-NOP was approved for use in Canadian cows last January, and its producer was still ramping up its production, McAllister said. While it appears to be consistent at reducing methane emissions from cows, it’s less consistent at boosting a cow’s feed efficiency, which could hold back its adoption.
“You can’t expect producers to adopt technology that costs them money but doesn’t have any economic return,” McAllister said.
Seaweed was another popular methane-reducing additive, McAllister said. Certain types of seaweed contain a substance called bromoform that inhibits methane production in cows. The Calgary-based company Synergraze was developing a seaweed-based additive that can reduce methane production by about 90 per cent.
The challenge of seaweed was scaling it up, McCallister said.
“We don’t want people harvesting it from pristine environments,” he said, and you need a giant heated saltwater pool if you want to grow it inland.
“That’s going to be pretty expensive.”
McAlliser encouraged farmers to check the science behind any new methane-reducing additives before feeding them to their cows.
Farmers also have to ensure they feed cows the right way, added Robinson. If you feed your cows barley and don’t grind it just right, for example, your cows won’t digest it properly and will grow more slowly, resulting in more carbon per cow.
“You can have the best feed in the world, but if it’s not mixed and delivered in a timely fashion, you’re still going to screw things up.”
