Glyphosate-tolerant corn: The composition and feeding value of grain from glyphosate-tolerant corn is equivalent to that of conventional corn (Zea mays L.)

Glyphosate-tolerant (Roundup Ready) corn line GA21 has been developed by ge netic modification to tolerate glyphosate, the active ingredient in Roundup herbicide. The purpose of this study was to evaluate the compositional and nutritional safety of corn line GA21 compared to that of conventional corn . Compositional analyses were conducted to measure proximate, fiber, amino acid, fatty acid, and mineral contents of grain and proximate, fiber, and m ineral contents of forage collected from 16 field sites over two growing se asons. The nutritional safety of corn line GA21 was evaluated in a poultry feeding study conducted with 2-day old, rapidly growing broiler chickens, a t a dietary concentration of 50-60% w/w. Compositional analysis results sho wed that, except for a few minor differences that are unlikely to be of bio logical significance, the grain and forage of GA21 corn were comparable in their composition to that of the control corn line and to conventional corn . Results from the poultry feeding study showed that there were no differen ces in growth, feed efficiency, adjusted feed efficiency, and fat pad weigh ts between chickens fed with GA21 grain or with parental control grain. The se data taken together demonstrate that Roundup Ready corn is as safe and n utritious as conventional corn for food and feed use.