DAVIS: A scientist guides a long tube through the mouth and into the stomach of Thing 1, a two-month-old calf who is part of a research project to stop cows from belching methane, a powerful gas greenhouse.

Paulo de Meo Filho, a postdoctoral researcher at the University of California, Davis, is part of an ambitious experiment to develop a pill to transform cows’ gut bacteria so that they emit less or no methane.

While the fossil fuel industry and some natural sources emit methane, cattle farming has become a major climate concern due to the sheer volume of emissions from cows.

“Almost half of the (global) temperature increase we’ve experienced so far is due to methane,” said Ermias Kebreab, a professor of animal sciences at UC Davis.

Methane, the second largest contributor to climate change after carbon dioxide, breaks down faster than CO2 but is more potent.

“Methane lives in the atmosphere for about 12 years,” unlike carbon dioxide which persists for centuries, Kebreab explained.

“If you start reducing methane now, we can see the effect on temperature very quickly.”