Mexican researchers discover that tropical leaves could reduce methane emissions in cows, a major contributor to climate change. Bob Mezan reports.
Livestock are responsible for 44 percent of all human-caused methane - a gas that is a major contributor to climate change. The cows emit the gas mainly through belching, a side effect from the fermantation of the grasses they eat. But now researchers in Mexico have discovered a new approach to reducing the animals' methane emissions by supplementing their feed with tropical leaves and flowers. Researchers from the Autonomous University of the State of Mexico have found that leucaena trees and cosmos flowers - plants native to Mexico - both have a methane-reducing effect. Containing an element called tannin, the plants kill bacteria and disrupt the fermentation process, resulting in 36 percent less methane emmission. SOUNDBITE: (Spanish): Octavio Castelan, Head of the Cattle and Environment Laboratory for the Autonomous University of the State of Mexico, saying: "One of the important things with this diet is that it doesn't reduce the productivity of the animal. It is an important element because farmers could say with the diet it could reduce milk or less meat. We have demonstrated that it is not like this." Scientists hope the cost-effectiveness of using locally-sourced leaves would mean that more farmers take up the new diet.