Improvements in the efficiency of animal agriculture over recent decades have dramatically reduced greenhouse gas emissions created by livestock, according to Dr. Frank Mitloehner, professor and air quality specialist in the department of animal science at University of California-Davis.

Mitloehner says that, despite widespread belief, the animal agriculture industry is not a major producer of greenhouse gases. Only 4.2 percent of the total greenhouse gases in the U.S. comes from the livestock sector, he said. Rather than livestock production, the greatest human contributor to climate change, he said, is fossil fuel use.

“Over (recent) decades, we have found that our livestock and feed sectors have become much more efficient,” said Mitloehner, who recently published a white paper titled “Livestock’s Contributions to Climate Change: Facts and Fiction.”

Advances in technology, nutrition, genetics

Advances in technology, nutrition and genetics have been “huge strides” forward for animal agriculture, he said.

“I’m not saying we are at the end of where we can be, but we have made huge advancements,” he said.

Mitloehner said the technology used in feed mills has become much more energy efficient, the industry has learned to control animal diseases and cut down on parasites, feed efficiency has increased, and there have been improvements to genetics.

“The feed business in general has developed technology to keep animals healthier or make them more efficient, helping reduce environmental footprint of herds,” he said. “The whole process of processing feedstuff has become much more efficient, and the carbon footprint of processing has been reduced dramatically.”

Mitloehner says the feed industry has been integral to the reduction in greenhouse gas emissions by the livestock industry.

“The feed industry is a driving force in this whole picture. Forty percent of the impact livestock has on the environment is based on the feed portion,” he said. “We have learned to improve or optimize the nutrients administered to our livestock.”

The use of materials in animal feed that Mitloehner says have no other use elsewhere, like nut hulls and almond shells, eliminates an environmental liability.

“We have learned to feed by-products from other crops that have no nutritional use to humans. By-products now have use in animal feed.” Ruminants, in particular, he said, are able to digest materials humans cannot, therefore making use of “a lot of products that cannot be used for human nutrition in any other way.”

“We are able to feed a lot of commodities that have no other use and would only be an environmental liability if we weren’t using it for livestock feed,” he said.