Do GMO Feeds Harm Livestock?

Scientific review shows no adverse effects of feeding genetically-engineered feeds to livestock.

Burt Rutherford, Senior Editor

September 24, 2014

2 Min Read
Do GMO Feeds Harm Livestock?
<p>Delivering feed</p>

There are a few hot-button issues that seem to be flash points in generating heated debate about the safety of our food supply. Perhaps one of the most volatile of those flash points is whether or not genetically engineered (GE) foods, often called genetically modified organism or GMOs, are harmful to human and animal health.

However, the debate over GMOs often seems to generate more heat than light. In an effort to bring some science to the fore, Gregory S. Lewis, Ph.D., editor-in-chief of the prestigious  Journal of Animal Science, invited Alison Van Eenennaam, cooperative Extension specialist in animal biotechnology in the Department of Animal Science at the University of California, Davis, to conduct a thorough review of the scientific literature and evaluate the effects of GE feed ingredients on the animals consuming those feeds.

And the result? “The scientific evidence indicates clearly that the health, wellbeing, and productivity of animals consuming GE feeds are at least comparable to those of animals consuming conventional feeds,Lewis says.

In a thorough review of scientific literature and field data sets, an article published in the peer-reviewed Journal of Animal Science documents evidence that the performance and health of food-producing animals fed GE crops are comparable with those of animals fed non-GE crops.

Since their introduction in 1996, GE feed crops have become an increasing component of livestock diets. Today, more than 95% of U.S. food-producing animals consume feed containing GE crops. Studies that involve feeding GE crops to livestock are used to evaluate the safety of these crops.

Recently, University of California, Davis researchers reinforced the consistency of these studies in an unprecedented review article that examines nearly 30 years’ worth of livestock-feeding studies, representing more than 100 billion animals.

In the review, posted online September 24 in the Journal of Animal Science, Van Eenennaam and research assistant Amy Young examine feeding data from 1983 (13 years before GE crops were introduced) through 2011 (when GE feed use exceeded 90%).

The review also examines the composition of products derived from animals fed diets containing GE feeds. “No study has revealed any differences in the nutritional profile of animal products derived from GE-fed animals,” state the authors.

The review, entitled "Prevalence and impacts of genetically engineered feedstuffs on livestock populations," will appear in print and open-access in the October 2014 Journal of Animal Science. Due to the high level of interest in the article, ASAS has elected to make the full article immediately available in open-access form at

“I believe that information in this peer-reviewed article is essential for open-minded discussions of GE feeds and foods, and we have made this information freely available to the public,” Lewis says.


Calf And Feeder Prices Widen Gap With Fed Cattle-Beef

55 Beef Cartoons From Leigh Rubin

Obama Administration Takes Aim At Antibiotic Resistance

4 Tips For Extending Fall And Winter Grazing

About the Author(s)

Burt Rutherford

Senior Editor, BEEF Magazine

Burt Rutherford is director of content and senior editor of BEEF. He has nearly 40 years’ experience communicating about the beef industry. A Colorado native and graduate of Colorado State University with a degree in agricultural journalism, he now works from his home base in Colorado. He worked as communications director for the North American Limousin Foundation and editor of the Western Livestock Journal before spending 21 years as communications director for the Texas Cattle Feeders Association. He works to keep BEEF readers informed of trends and production practices to bolster the bottom line.

Subscribe to Our Newsletters
BEEF Magazine is the source for beef production, management and market news.

You May Also Like