Cows can produce up to 200 liters of methane every day and there are an estimated 1.4 billion of them in the world, so figuring out a way to reduce those emissions could potentially help address some climate-change concerns.
In the past, scientists have tried to introduce bacteria from kangaroos into cows, in hopes of reducing methane emissions from cows. In 2004 in the United States, manure and expelled body gas from livestock (predominantly cows and pigs) contributed more than 13 millions tons of methane, according to a 2014 study published in the Journal of Geophysical Research: Atmospheres. To put that figure into context, oil and gas operations contributed 7 million tons of methane.
This kind of research could also be important to farmers, Munn said. When the bacteria break down food into methane, they’re essentially robbing the cow of some of the food’s nutrients. If farmers could somehow reduce methane emissions from livestock, more nutrients would go to the cow itself, which could help them grow better.