No Differences in Livestock Eating GMO Food, Review Finds

Livestock raised on feed that contains genetically modified ingredients—in other words, approximately 95 percent of the food-producing animals in the U.S. today—show no signs of differences in performance or health, according to a new study from researchers at the University of California-Davis. They also found no differences in the nutritional makeup of the food products derived from these animals.

“Studies have continually shown that the milk, meat, and eggs derived from animals that have consumed GE feed are indistinguishable from the products derived from animals fed a non-GE diet,” says lead author Alison Van Eenennaam, PhD, a food scientist at UC-Davis. “Therefore, proposed labeling of animal products from livestock and poultry that have eaten GE feed would require supply chain segregation and traceability, as the products themselves would not differ in any way that could be detected.”

Dr. Van Eenennaam and her colleagues reviewed livestock-feeding studies dating back to 1983, through the introduction of GE crops in 1996, and subsequently through 2011, a period with high levels of predominately GE animal feed. They also collected information from publicly available USDA field data sets, representing some 100 billion animals.

“This data is basically a reflection of the field experience of feeding food-producing animals,” says Dr. Van Eenenaam. “They don’t show any trend suggesting a change in the health parameters or productivity of any of these animals subsequent to the introduction of genetically modified feed. If these things were happening, you’d expect to see changes in the food-to-gain ratios or increases in the post-mortem condemnation rates, but none of that happened. While this is not a controlled study, it’s a very large set of field observations that supports the findings of the many studies we reviewed.”

Dr. Van Eenenaam stressed that the research was not supported by industry in any way, but solely through university funding.