University of Illinois

No. 4/April 17, 1998

Bt-Corn and Livestock

I have received a handful of reports about growers concerned that cattle and hogs are not consuming Bt-corn, either in feed or as they forage in the fields. During the weeks of April 6 and April 13, several of these reports rolled into my e-mail in-box, and I get the sense that what might have begun as testimonial or rumor has taken on the cloak of "fact." Rick Weinzierl, Extension entomologist in the Department of Crop Sciences, also has received at least one report that cows are not eating Bt-corn stalks, and may be eating less ground ear corn, whole shelled corn, or ground shelled corn from hybrids that express the Bt endotoxin.

Rick and I both have replied to these questions by stating that none of the scientific literature supports the claim that cattle and hogs will not eat or will eat less Bt-corn. Nor has either of us heard this issue discussed at the many meetings we have attended. Not much, if any, Bt endotoxin is produced in the grain of Bt-corn hybrids. We believe that this issue is based upon rumor and should be given no credence unless scientifically proven otherwise.

Kevin Steffey (, Extension Entomology, (217)333-6652