When looking into the big, docile eyes of the domestic cow, it is hard to imagine that something sinister lurks beneath the surface. That is, until they burp. Cows are prolific producers of methane, a greenhouse gas that is 25 times more powerful than carbon dioxide at the same volume. In an effort to help curb global warming, a team of researchers at the University of Aberdeen is looking to see whether changing the diet or genetic makeup of the animals could help lower emissions. Their efforts are a part of the RuminOmics Project, a €7.7 million effort funded by the EU.
Methane is formed by bacteria in the guts of ruminant animals when they digest fibrous feed and is expelled into the atmosphere when cows belch. The scientists at the RuminOmics Project are investigating whether or not diet or genetics have a role to play in methane generation. They have already found that adjusting the feed in dairy cattlecan adjust methane levels. A study from Sweden found that increasing dietary protein in the feed lowered the amount of methane, but increased the levels of nitrogen in the urine which is lost as ammonia. Ammonia is also a source of pollution as it builds up in the soil and eventually becomes the greenhouse gas, nitrous oxide.
“Methane production represents a waste in feed energy, varying between two and 10 percent of total energy consumed by the animal. Methane production is important for cattle and sheep farmers because if the amount of methane produced can be lowered then there are benefits for the environment, production, and profitability.” says Professor John Wallace of the University of Aberdeen.
The RuminOmics research also suggests that some individual cows are either low or high methane emitters regardless of diet. To investigate this hypothesis, the group has begun testing 25 diary cattle and will later expand to a test group of 1,400. Preliminary results suggest that regardless of feed, some cows create more methane. This information could be helpful in selectively breeding stock that are low emitters of both methane and nitrogen.
However, while any steps to help curtail climate change are important, it would perhaps be more efficient in the long run to eat significantly less red meat and fewer dairy products. The cheap and readily available nature of beef has not only affected our bodily health, but that of the planet. With developing nations beginning to see a shift in their diets towards more meat consumption, the risk of warming the planet through agricultural practices will increase. It is up to the choices of entire populations whether or not to reduce emissions not just through infrastructure and electricity-generation, but through what is included on the menu.
Images via USDA.