A new study http://www.sciencedirect.com/science/article/pii/S2211912416300013 by the Food and Agricultural Organization (FAO) finds that animals, particularly cattle, consume a lot less food that humans eat and less an environmental burden than previously reported.
That’s significant, because previous reports, such as FAO’s own “Livestock’s Long Shadow” issued a decade ago, suggested animals are consuming large amounts of food that could be eaten by humans and creating a huge carbon footprint.
Previous studies, often cited without question, suggest that between 12 and 45 lb of grain are needed to produce 1 lb of beef. “Contrary to these high estimates, the current investigation found that an average of only 6.6 lb of cereals are need to produce 1 lb of meat,” says Anne Mottet, a co-author of the FAO study. “Cattle only need 1.3 lb of protein from human food to produce 2.2 lb of protein in meat and milk, which is of higher nutritional value.
“In addition, this study determined that 86% of livestock feed, which includes residues and by-products, is not suitable for human consumption,” says Mottet. “If not consumed by livestock…, these ‘leftovers’ could quickly become an environmental burden as the human populations grows and consumes more and more processed food.
“Animal production, in its many forms, plays an integral role in the food system, making use of marginal lands, turning co-products into edible goods, contributing to crop productivity and turning edible crops into highly nutritious, protein rich food,” she says.