1.17—Fast growing birds can eat Liberty-Link Corn

Several safety studies have been carried out with Liberty-Link (LL) GM maize and these provide assurance of its safety.

See Genetic Roulette’s False Claims at Bottom of Page

Analysis of Peer-Reviewed Research:

This is another example of Smith being so anxious to make a case against GM crops that he misinterprets as a problem an observation that is evidence of safety.  The death rate in this report was normal for poultry research facilities and demonstrates that no meaningful biological difference exists between the control corn and experimental GM corn.  What’s more, in the decade since this corn variety was registered, several other LL corn varieties have been commercialized. Regulatory scrutiny of these LL corns required extra feeding trials (with both rats and farm animals) that Smith does not mention. This extensive history of laboratory testing, and practical experience in the meat and poultry industry stretching out more than ten years, provides additional assurance about the safety of LL corn going far beyond the case taken up by Smith.

1. The reported mortality was normal for this poultry research facility. Smith does not give credence to a prominent statement in the scientific report saying “Mortality was normal for this fast-growing strain of bird, where at our research facilities we normally see values of 5 percent to 8 percent in male broilers.”

2.  Regulatory authorities interpreted the study to show no difference between GM and Non-GM varieties. This scientific study mentioned by Smith has been assessed by Food Standards Australia New Zealand (FSANZ) as supporting the conclusion that there are no biologically significant differences between the LL GM corn line and other commercial varieties of corn.

3. Scientific studies on this corn not cited by Smith also show no adverse effects. More than three other animal feeding studies on the same type of GM corn have been published by other research groups, all providing assurance that the GM corn was as safe and nutritious as conventional corn, but none of these other studies are mentioned by Smith. One of the recent studies (Jacobs and others 2008) was carried out using chickens and no differences were seen in chicken growth responses between genetically modified and non-genetically modified corn.


FSANZ (June 2003) Food derived from glufosinate-ammonium tolerance corn line T 25 . A safety assessment. Technical Report Series Number 23. Food Standards Australia New Zealand .

He XY, Huang KL, Li X, Qin W, Delaney B, Luo YB (2008)  Comparison of grain from corn rootworm resistant transgenic DAS-59122-7 maize with non-transgenic maize grain in a 90-day feeding study in Sprague-Dawley rats. Food and Chemical Toxicology. 46(6):1994-2002. Epub 2008 Feb 2. A recent example of several safety recent studies on Liberty Link (glufosinate tolerant) type corns.

Hérouet C, Esdaile DJ, Mallyon BA, Debruyne E, Schulz A, Currier T, Hendrickx K, van der Klis RJ, Rouan D (2005) Safety evaluation of the phosphinothricin acetyltransferase proteins encoded by the pat and bar sequences that confer tolerance to glufosinate-ammonium herbicide in transgenic plants. Regulatory and Toxicological Pharmacology 41(2):134-49. Scientific review of the safety arguments for the herbicide tolerant protein in Liberty Link crops.

Jacobs CM, Utterback PL, Parsons CM, Rice D, Smith B, Hinds M, Liebergesell M, Sauber T (2008) Performance of laying hens fed diets containing DAS-59122-7 maize grain compared with diets containing nontransgenic maize grain. Poultry Science 87(3):475-9.  Another example of successful poultry feeding experiments with Liberty Link (glufosinate tolerant) corn.

Leeson S. (1996) The effect of glufosinate resistant corn on the growth of male broiler chickens. Report prepared for the company AgrEvo on the equivalence of genetically modified Liberty Link corn to conventional corn in chicken feeding trials by Dr Leeson of University of Guelph Canada. www.foe.co.uk/resource/evidence/chicken_study.pdf pdf file accessed Dec 7 2008

Genetic Roulette Falsely Claims:
Twice the number of chickens died when fed Liberty Link corn

1. The death rate of chickens fed Chardon LL GM corn for 42 days was 7 percent, compared to 3.5 percent among controls.

2. GM-fed chickens also had more erratic body weight and food intake, and less weight gain overall.

3. This study was designed so that only huge differences would be statistically significant.

4. The results were therefore dismissed without follow-up.

Genetic Roulette highlights one animal-feeding study carried out with chickens where greater numbers of chickens died following the feeding of genetically LL modified maize (7 percent) compared to lower deaths in a group fed conventional diet (3 percent).