Scientists say new study shows pig health hurt by GMO feed

June 11 Tue Jun 11, 2013 3:42pm EDT

June 11 (Reuters) - Pigs fed a diet of only genetically modified grain showed markedly higher stomach inflammation than pigs who dined on conventional feed, according to a new study by a team of Australian scientists and U.S. researchers.

The study adds to an intensifying public debate over the impact of genetically modified crops, which are widely used by U.S. and Latin American farmers and in many other countries around the world.

The study was published in the June issue of the peer-reviewed Journal of Organic Systems by researchers from Australia who worked with two veterinarians and a farmer in Iowa to study the U.S. pigs.

Lead researcher Judy Carman is an epidemiologist and biochemist and director of the Institute of Health and Environmental Research in Adelaide, Australia.

The study was conducted over 22.7 weeks using 168 newly weaned pigs in a commercial U.S. piggery.

One group of 84 ate a diet that incorporated genetically modified (GM) soy and corn, and the other group of 84 pigs ate an equivalent non-GM diet. The corn and soy feed was obtained from commercial suppliers, the study said, and the pigs were reared under identical housing and feeding conditions. The pigs were then slaughtered roughly five months later and autopsied by veterinarians who were not informed which pigs were fed on the GM diet and which were from the control group.

Researchers said there were no differences seen between pigs fed the GM and non-GM diets for feed intake, weight gain, mortality, and routine blood biochemistry measurements.

But those pigs that ate the GM diet had a higher rate of severe stomach inflammation - 32 percent of GM-fed pigs compared to 12 percent of non-GM-fed pigs. The inflammation was worse in GM-fed males compared to non-GM fed males by a factor of 4.0, and GM-fed females compared to non-GM-fed females by a factor of 2.2. As well, GM-fed pigs had uteri that were 25 percent heavier than non-GM fed pigs, the study said.

The researchers said more long-term animal feeding studies need to be done.

Biotech seeds are genetically altered to grow into plants that tolerate treatments of herbicide and resist pests, making producing crops easier for farmers. Some critics have argued for years that the DNA changes made to the transgenic plants engineer novel proteins that can be causing the digestive problems in animals and possibly in humans.

The companies that develop these transgenic crops, using DNA from other bacteria and other species, assert they are more than proven safe over their use since 1996.

CropLife International, a global federation representing the plant science industry, said more than 150 scientific studies have been done on animals fed biotech crops and to date, there is not scientific evidence of any detrimental impact.

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Comments (5)
Tonyscomments wrote:
we aren’t the US pigs getting sick now then? Did they use isogenic corn or soybeans grown in the same field – there are more differences in nutiry=tional content between corn grown in different fields than between Gm and non_GM corn. Did they cook the soy – you can’t just feed soy directly to pigs – do they know that?

Jun 11, 2013 4:18pm EDT  --  Report as abuse
Tonyscomments wrote:
the journal is run by a company Organic Systems Inc and has more geologists than biologists on its management – what a load of crap they fifgure out the Monsanto gold – publish a paper against Monsanto nad watch the requests for reprints roll in. Do any of them have any expeinmece in toxicology methodology?

Jun 11, 2013 4:27pm EDT  --  Report as abuse
Tonyscomments wrote:
I think Monsanto should really start suing peopole who deceive and lie – mind you I fully expect the world’s scientists to review and discredit this one – it will take a year and the activist groups will raise more money. I would like a decent reserach team to do this study to put this beyond any further doubt – there have been some already but they get ignored. This si how you do the study take corn or soy with the trait and the isogenic coprn or soy without the trait and grow them side by side radomized in a field – harvest the grain and process teh same. Then take about 100 animals each and treat with x1 x2 x3 the amount fo corn or soy into the diet. Then repeat and get teh same result with a stats analysis aty p value

Jun 11, 2013 4:31pm EDT  --  Report as abuse
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