This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the November 2017 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.

The rumen allows cattle to make highly nutritious beef out of things that humans can’t even digest. Rumen microbes have digestive enzymes that mammals don’t. This allows rumen microbes to break down complex feeds into very simple molecules, and reassemble those molecules into volatile fatty acids that the animal can absorb and use as an energy source. These microbes can also take some simple nitrogen-based compounds like ammonia and urea, turn them into amino acids, and assemble those amino acids into microbial proteins that the animal can digest and absorb. But the rumen can be wasteful as well. Some rumen microbes assemble carbon (C) and hydrogen (H) molecules together into methane (CH₄) instead of volatile fatty acids. The animal can’t absorb or use methane, so methane gets belched out. This can waste significant feed energy – methane is the main ingredient in natural gas, after all. If we can find a way to reduce methane production in the rumen, we may be able to further improve feed efficiency and shrink beef’s environmental footprint at the same time.

Continue reading →