Producing "green" meat
In December 2011, Washington State University animal scientist Jude Capper published a paper in the Journal of Animal Science showing that beef production has become more efficient and reduced pressure on the environment since 1977.
“Consumers often perceive that the modern beef production system has an environmental impact far greater than that of historical systems, with improved efficiency being achieved at the expense of greenhouse gas emissions,” wrote Capper.
In fact, green house gas emissions from beef production have decreased over the last 30 years. To produce one billion kilograms of beef, producers now use 69.9 percent of the animals, 81.9 percent of the feedstuffs, 87.9 percent of the water and 67.0 percent of the land that they did in 1977. Along with that increase in efficiency came an 18.1 percent decrease in manure, a 17.3 decrease in methane and a 12 percent decrease in nitrous oxide emission.
“Gains in productive efficiency allow increases in food production to be achieved concurrently with reductions in environmental impact,” wrote Capper. “As the U.S. population increases, it is crucial to continue the improvements in efficiency demonstrated over the past 30 years to supply the market demand for safe, affordable beef while reducing resource use and mitigating environmental impact.”
Overall, the carbon footprint per billion kilograms of beef decreased 16.3 percent between 1977 and 2007.
Many animal scientists are bringing attention to how increasing feed efficiency can reduce the environmental impact of animal agriculture. In the July, 2011 issue of Animal Frontiers, Aarhus University researchers John Hermansen and Troels Kristensen looked at life cycle assessment (LCA) studies, which tracked carbon output through meat and dairy production. The LCA studies include analyses of livestock management steps like feed transportation, manure handling, and meat and milk production.
In meat production, Hermansen found, farmers should try to use less feed to raise livestock. “In order to reduce the carbon footprint of the livestock products, farmers should draw very much attention to the overall feed efficiency,” said Hermansen in an interview with the American Society of Animal Science. This viewpoint is backed by studies showing that in pig farms where the ratio of feed to kilogram of body weight gain was less, the carbon footprint was reduced by 10 percent. Increased feed efficiency was also important in dairy farming, where increased milk production per cow markedly reduced the carbon footprint.
The decreased environmental impact is a combination of many factors, from better disease management to better transportation systems, but feed efficiency was important.
“It’s sort of a double-whammy,” said Nancy Morgan, a liaison to the World Bank and economist with the Food and Agriculture Organization of the United Nations. “If you could increase productivity, rather than increasing the number of animals, you’re producing less green house gases.”