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There were no compositional data at all on milk or meat from offspring of cloned


Published Cattle Data Not Considered by FDA

After the FDA Clone Risk Assessment was published, a carefully controlled French study compared health, milk and meat parameters on 37 Holstein clones and 38 were breed, age and sex-matched contemporary control animals that were kept under the same conditions at the same experimental farm where the clones were kept (Heyman et al., 2007). In this carefully controlled experiment, the French scientists detected subtle difference between clones and the comparators. Heyman et al. (2007) noted that previous work on composition of milk or meat from SCNTs had not found “obvious differences,” but pointed out that these studies either involved a very small number of animals (e.g. Takahashi and Ito, 2004; Tian et al. 2005) or were not carefully controlled as environmental conditions and herd management can contribute to the variability of the data (e.g. Walsh et al., 2003).

The larger sample sizes and more carefully controlled conditions French study make it more scientifically rigorous. For the milk quality study, Heyman et al (2007) compared the fatty acid composition of milk at days 80 and 180 of lactation of 5 cloned cows and 5 comparator cows. For the meat composition study, they sampled semitendinosus muscle at 8, 12, 18 and 24 months of age from nine cloned heifers and eight control heifers. Walsh et al. (2003) had found significant differences in fatty acid profiles of milk (particularly levels of palmitic acid and linolenic acid), but pointed out that since the comparator animals were not born on the same farms or fed the same diets, they concluded that the differences were not meaningful. Interestingly, Heyman et al. (2007) found “differences in the fatty acid composition of milk and muscle arising from two families of clones” (Heyman et al., 2007: 134). Furthermore, rats fed the milk or meat from the clones showed no difference in allergenicity of these products, no detection of IgE antibiodies nor significant differences in antibodies for IgG, IgA and IgM compared to control rats. Rather then conclude that there is no potential allergenicity problem, the French scientist instead point out the problems with their test and call for further research in this area to fully answer the question: “we cannot exclude that some allergic response could be detected using different non-consanguinus strains of rats. Moreover, allergic responses markedly differs between human and animals; therefore, the above results, instead of being fully conclusive about the lack of allergenicity of products (milk, meat) from clones, provided strong support for the need for more comprehensive analysis of risks related to potential allergenicity” (Heyman et al., 2007: 139). Unlike the FDA’s Risk Assessment, this French study realizes the complexities involved and calls for further research.

In sum, given the paucity of data on SCNT cattle and the lack of any data at all on offspring as to milk and meat composition, the available data are not adequate to draw conclusions about safety.

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