Impact of the elimination of animal agriculture in the US
by Michael Azain
ASAS Public Policy Committee
A recent paper in the Proceedings of the National Academy of Science examined the impact that eliminating animal agriculture in the US would have on food production and greenhouse gas (GHG). The authors, Robin White from Virginia Tech and Mary Beth Hall from the USDA ARS, stated that the rationale for the study was the perception that animal agriculture contributes to GHG, and that feedstuffs consumed by animals adds to food insecurity. The authors concluded that while eliminating animal agriculture would result in a 23% increase in food (largely accounted for by increased corn and legumes), it would “create a food supply incapable of supporting” the nutrient requirements of the US population. Animal products currently account for almost half of our protein supply, a majority of our essential fatty acid requirement, and are significant sources of many micronutrients. The assessment found that elimination of animal agriculture would reduce agricultural GHG emission by 28%. Currently, animals account for about half of the GHG attributed to agriculture and about 3% of the total US GHG. The explanation as to why elimination of animals did not reduce GHG by half was that animals contribute to agriculture and society in other ways. Animal agriculture supplied 4 million metric tons of fertilizer used in plant production, and replacing this resource with industrial fertilizer offset some of the GHG benefit. In addition, animals consume over 40 million metric tons of byproducts generated by humans that would need to be disposed of in other ways that generate GHG. Based on US EPA data, all of agriculture accounts for 9% of US GHG. Elimination of animal agriculture would be estimated to reduce total emissions by 2.6%.
It is important to note that this study models the impact of eliminating animal agriculture and reports expected outcomes. As animal scientists use this report to explain and defend our industry, we can show that while animals are competing with humans for food, the result of shifting entirely to a plant based diet would result in some increase in food supply and a small decrease in environmental impact, but would also result in a major increase in nutritional deficiencies in the population. Other factors should also be considered. Animal industries employ over a 1.5 million people and contribute billions of dollars to our economy. The role of economics in all of agriculture as the basis for what gets produced was not part of this model, but is critical for both the producer and consumer.