The National Corn Growers Association (NCGA) notes studies continue to show that animals fed biotech corn and the meat, milk and eggs from those animals perform to the same level as their non-biotech fed counterparts.

In a joint research project from the University of Nebraska and University of Illinois researchers compared the performance and carcass characteristics of feedlot steer that were fed glyphosate-tolerant (Roundup-Ready events GA21 or kn603) corn and reference hybrids. Their results, published in Journal of Animal Science, volume 81, indicate performance in the two feeding classes was the same.

This project examined more than 550 head of beef steers in feedlot conditions and looked at dry matter intakes, average daily gains and feed efficiencies of cattle fed biotech and non-biotech corn, and found no significant differences in either the treatment or control cattle.

After harvest, no differences were observed in carcass weight, the ribeye area or marbling scores, according to the study. The researchers stated in their abstract that due to these results, insertion of glyphosate-tolerant genes had no significant effect on nutritive quality of corn. Performance and carcass characteristics were not influenced, which suggests that Roundup Ready corn is similar to conventional, non-transgenic corn when fed to finishing cattle, according to the study.

A Japanese study published in the same volume of the Journal of Animal Science also focused on biotech corn. However, this study looked at the detection of corn intrinsic and recombinant DNA fragments and Cry1 Ab protein in the gastrointestinal contents of pigs fed genetically modified corn Bt11.

“This study is very significant as the Japanese National Institute of Animal Health, National Food Research Institute, and the National Institute of Livestock and Grassland Science were joint investigators in the research,” said Tracy Snider, Manager of Livestock Information and Programs. “There have been hundreds of trials in the United States showing the safety of biotech corn in animal rations, however foreign countries are beginning to test for their own knowledge, the safety of biotech corn.”

The results of Japanese study suggest there is no difference in the general health and growth rate of biotech and non-biotech corn-fed control pigs. The research also showed intrinsic genes, or recombinant sequence corn-derived DNA, are largely degraded in the gastrointestinal tract. Some of the fragmented corn DNA were still detectable; however, the study concluded that scant amounts could be excreted, and the environmental effects would be negligible.