GMO Meat: Livestock and GM Crops

Week #10 - If livestock eat genetically modified grain, will there be GMOs in my meat?

In the United States, livestock have been consuming feed made from GM crops for almost twenty years. More than two-thirds of GM corn and half of GM soybeans are used for livestock feed. In that time, GMOs have never been detected in the milk, meat or eggs derived from animals fed GM feed.

First, it’s important to understand that almost all the food that we (or animals) eat contains DNA and proteins. The DNA and proteins found in food, GMO and non-GM, are released from the food and processed by the digestive system in our gastrointestinal tract.  During digestion, GMO and non-GMO DNA is broken down into the four nucleotides that make up all DNA, and/or into small nucleotide fragments.  Similarly, proteins, again GMO and non-GM, are broken down into one or a few of the 21 amino acids that exist in nature.  Many, many studies have been conducted on the potential for GMO DNA or proteins to be transferred into animal tissues.  No intact or immunologically reactive protein or DNA has been detected in animal tissue

Therefore, as Alison Van Eenennaam, extension specialist in animal genomics and biotechnology at the University of California, Davis, explains, “Genetically engineered crops are digested by animals in the same way as conventional crops. Evidence to date strongly suggests that feeding livestock with genetically engineered crops is equivalent to feeding unmodified feed sources in terms of nutrient composition, digestibility and feeding value.”  Additionally, Dr. Van Eenennaam states, “Genetically engineered DNA, or the novel proteins encoded in therein, have never been detected in the milk, meat or eggs derived from animals fed genetically engineered feedstuffs. Several studies have documented that small fragments of plant-derived, but not genetically engineered, DNA can pass into the tissues of animals that consume the plants.”

 

Are  feeds made from GMOs safe for livestock?

 

GM crops, such as corn, soy and alfalfa, are commonly used for livestock, and more than 100 digestion and feeding studies have been conducted with food-producing animals, like beef cattle, swine, sheep, lactating dairy cows and chickens.

In a post for Facts About Beef, Ruth McDonald, professor and chair of food science and human nutrition at Iowa State University points out  that “GM products have been in the U.S. food supply since 1996—hence we have years of practice that have shown no negative impact on animal or human health. Farm animals, the most carefully monitored animals on the planet, have been raised on GM corn and soybeans over several generations and there is no evidence of negative effects on growth, reproduction or disease. And there has been no documented case of human illness or allergen associated with GM foods.”

For additional information, we recommend these articles and answers: