Chardon Report I - Non-Suitability of Genetically Engineered Feed for Animals

Report I, May 2002 


[PDF version of the full report (429KB)]

1. Introduction

Chardon LL is intended to be fed, as a whole plant, to cattle. No experiments on the suitability of such a diet have been made. Approval of the application of Aventis for commercial growing of this maize in the United Kingdom was granted on the basis of two animal-feeding experiments, one on the feeding of maize kernels to chickens and the other on the feeding of the isolated GM protein to rats. In both experiments, the investigators concluded that the tested animals consumed food and gained weight normally. The present report re-analyses the data and reaches a different conclusion.

2. Experiment on feeding of glufosinate-resistant maize to chickens

The stated conclusion of the official report is: ‘Results of live bird traits … show that source of corn … had no effect on body weight, feed intake, … or percent mortality over the experimental period …’ We point out, however, that although the body weights of the GM-fed and control group never differed by as much as 1%, the errors quoted (or deviations from the average: the meaning of these figures was not stated), which were initially the same, grew much more rapidly for the GM-fed group until they were 2.5 times greater by the end of the experiment (day 42) This signals erratic weight-gain in the GM-fed chickens. Daily food-consumption was at first greater for the GM-fed chickens, then fell below that of the control group. Again, the ‘error bar’’ increased with time until they were 3.4 times greater for the GM-fed birds. Furthermore, the mortality rate amongst the GM-fed chickens was twice that for the control group, although the study considered the rates to be normal at that laboratory.

3. Experiment on feeding of PAT-protein to rats

The purpose of this experiment was to demonstrate non-toxicity to human beings. It was not maize but the isolated GM protein (PAT protein), derived from oilseed rape, that was added to the diets of rats. Four groups of young rats were used, which would have a rapid growth rate. Each group was subdivided into 5 males and 5 females. Two control groups ate, respectively, a normal laboratory rat diet and a diet containing a prescribed amount of soya. Two ‘treated’ groups ate, respectively, a diet low in PAT-protein or high in PAT-protein; but in both cases the total amount of protein was adjusted with the addition of soya to equal the amount in the control diets.

The weights, food consumption and various biochemical and physiological quantities were monitored on 5 days of the 14- (or 13-)day experiment. No toxic reactions were expected and it was therefore felt that this length of study would be sufficient, somewhat pre-empting the outcome. We re-examined the data on weight gain and food consumption.

The stated conclusions of the study are that ‘Average mean food consumption over treatment was in the same range for treated groups and controls’; that ‘Occasionally recorded differences between controls and treated groups were generally small, showed no dose-relationship or consistent trend’ and ‘Mean body weights were similar for treated groups and controls.’ Our conclusion, to the extent that conclusions can be drawn from this study, are different. Graphs of individual body weights show that some rats in the PAT-protein groups were not gaining weight as rapidly as those in the control groups, and the feeding patterns were erratic in the PAT-protein groups. If the average rate of weight gain is calculated as (weight on last day minus weight on first day) divided by (number of days of experiment), the results are as follows:


Average rate of weight gain (gm/day)
Control group on normal laboratory diet:
Control group on diet with soya
Treated group on low PAT-protein
Treated group on high PAT-protein


These averages indicate that some rats on the GM diet were not thriving as well as those on the non-GM diet.

4. Stray cattle did not eat GM maize

A trial of GM forage maize having the same genetic construct as Chardon LL was damaged by cattle straying into the field. However, there was no evidence that the cattle had eaten any of the maize.

5. Anecdotal evidence on animals’ response to genetically modified feed

An American journalist gathered anecdotes about the response of animals to GM feed and crops, including the following.

  • Hogs would not eat the ration when GM crops were included.
  • Cattle broke through a fence to eat non-GM hybrids but would not touch the GM Round-up Ready corn, even though they had to wade through it to reach the hybrids.
  • An organic farmer found deer eating-up his soya beans, while across the road there was not one consuming the Round-up Ready soya beans.
  • Raccoons by the dozen were found eating the organic corn, while down the road there was not one ear that had been touched in the Bt fields.

Various scientists in the United States reported difficulties with the feeding of GM maize to cattle. Generally, the reports concern Bt maize. Typically, a farmer buys a new shipment of maize, which his cattle either refuse to eat or eat with reduced consumption. Upon making enquiries, he discovers that the maize is a genetically modified variety. When he replaces it with a non-modified maize, the cattle start eating again.

6. Conclusions of this report

On the basis of the evidence available, there is reason to be concerned that the genetically modified maize Chardon LL may have adverse effects on cattle and chickens, which are expected to consume this variety.