Glyphosate-Tolerant Corn:  The Composition and Feeding Value of Grain from Glyphosate-Tolerant Corn Is Equivalent to That of Conventional Corn (Zea mays L.)

Abstract

Glyphosate-tolerant (Roundup Ready) corn line GA21 has been developed by genetic 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 mineral contents of forage collected from 16 field sites over two growing seasons. The nutritional safety of corn line GA21 was evaluated in a poultry feeding study conducted with 2-day old, rapidly growing broiler chickens, at a dietary concentration of 50-60% w/w. Compositional analysis results showed that, except for a few minor differences that are unlikely to be of biological 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 differences in growth, feed efficiency, adjusted feed efficiency, and fat pad weights between chickens fed with GA21 grain or with parental control grain. These data taken together demonstrate that Roundup Ready corn is as safe and nutritious as conventional corn for food and feed use.

Performance of growing–finishing pigs fed diets containing Roundup Ready wheat (MON 71800), a non-transgenic genetically similar wheat, or conventional wheat varieties

“…A number of other studies with a range of species that have compared the growth performance of animals fed Roundup Ready corn or soybean meal with that of animals fed the non-transgenic genetically similar or conventional commercial varieties have shown no negative impact on growth. This included studies with broiler chicks (Sidhu et al, 2000;Stanisiewski et al, 2001;Taylor et al, 2003a and2003b), and with rats, catfish and dairy cows (Hammond et al, 1996). The differences in growth performance observed between the genders in the current study are similar to those of most other studies that have compared barrows and gilts (Labroue et al, 1994;Hyun and Ellis, 2001).…”

“…Carcass measurements were taken at 24 h post mortem and included carcass weight, carcass length (measured from the cranial tip of the aitch bone to the cranial edge of the first rib adjacent to the thoracic vertebra), midline fat depths (opposite the first rib, last rib and last lumbar vertebra), 10th rib fat depth (measured over the longissimus muscle at threequarters of the distance from the midline) and longissimus muscle area at the 10th rib. Subjective color, firmness and marbling scores were taken on the cut surface of the longissimus muscle at the 10th rib (NPPC, 1991 and2000).…”

“…The use of Roundup Ready wheat could provide the crop producer with flexible and broad-spectrum, post-emergence weed control. Glyphosate, which is the active ingredient in the herbicide Roundup, is one of the most widely used herbicides in the world (Sidhu et al, 2000). Therefore, Roundup Ready wheat (MON 71800) was developed to be tolerant to glyphosate by the Agrobacterium-mediated insertion of a DNA cassette containing the 5-enolpyruvylshikimate-3-phosphate synthase gene from Agrobacterium sp.…”

Reduced Fitness of Daphnia magna Fed a Bt-Transgenic Maize Variety

“…Adsorption and binding of Cry proteins to clay sometimes even enhance the insecticidal activity (Tapp and Stotzky 1995), thus increasing the likelihood that bioactive toxin is accumulated in the environment (Groot and Dicke 2002). At the same time, Bt-maize and isogenic controls have been corroborated to be substantially equivalent at the level of major nutrients and minerals and trace elements, both in kernels (Brake and Vlachos 1998;Sidhu et al 2000) and in the whole plant (Clark and Ipharraguerre 2001). Clark and co-workers found a negative trend in growth for the terrestrial isopod Trachelipus rathkii when fed different Bt-maize varieties compared to their isolines, but they could not find any negative effect of even high concentrations of purified bacterial Bt-toxin on the same test organism (Clark et al 2006).…”

The Safety of Genetically Modified Foods Produced through Biotechnology

“…Studies are performed to determine whether nutrients, vitamins, and minerals in the new food occur at the same level as in the conventionally bred food sources (e.g., see Berberich et al,1996;Sidhu et al, 2000). A typical example is the case of Roundup Ready soybeans.…”