Scientists say new study shows pig health hurt by GM feed

Study looked at 168 pigs over six months and found those fed genetically modified 
varieties of soy and corn had higher rates of severe stomach inflammation

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Pigs fed a diet of only genetically modified grain showed markedly higher stomach inflammation than ones which dined on conventional feed, according to a controversial new study.

The study was trumpeted by critics of GM crops, but proponents of biotechnology were equally quick to label the study as flawed.

The study by epidemiologist and biochemist Judy Carman was published in the June issue of the peer-reviewed Journal of Organic Systems Carman, director of the Institute of Health and Environmental Research in Adelaide, and other Australian researchers worked with two veterinarians and a farmer in Iowa to study a group of pigs raised in the U.S. The study was conducted over 22.7 weeks on 168 newly weaned pigs in a commercial American hog facility.

Half ate a diet that incorporated genetically modified (GM) soy and corn, while the other 84 pigs ate an equivalent non-GM diet. The corn and soy feed was obtained from commercial suppliers, the study said, and the pigs 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. However, those pigs on the GM diet had a higher rate of severe stomach inflammation — 32 per cent of GM-fed pigs compared to 12 per cent of non-GM-fed pigs. The inflammation was four times more likely in GM-fed males compared to non-GM-fed males, and more than twice as likely in GM-fed females versus non-GM-fed females. As well, GM-fed pigs had uteri that were 25 per cent heavier than non-GM fed pigs, the study said.

While the researchers said more long-term animal feeding studies need to be done, the Canadian Biotechnology Action Network said the research has lent “scientific credibility to anecdotal evidence from farmers and veterinarians, who have for some years reported reproductive and digestive problems in pigs fed on a diet containing GM soy and corn.”

Not so, charged a spokesperson for Monsanto Canada.

“The vast weight of scientific evidence gathered over hundreds of independent food and feed safety studies found no difference between animals fed GMO or non-GMO diets,” said Trish Jordan.

“For example, this study lasted about six months. Animals have been consuming GM crops and grains for more than 15 years.”

More than 150 scientific studies have been done on animals fed biotech crops and to date, there is no scientific evidence of any detrimental impact, said CropLife International, a global federation representing the plant science industry.

That’s likely to be ignored and the new study treated as “if it was sound science,” said Steven Yarrow, vice-president of CropLife Canada.

“It will be quoted over and over,” said Yarrow.

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