QPlease thoroughly explain the troubling findings of the recent, peer-reviewed journal, by Judy Carman et al., titled, "A long-term toxicology study on pigs fed a combined genetically modified (GM) soy and GM maize diet." Can you ensure the health and saf

Please thoroughly explain the troubling findings of the recent, peer-reviewed journal, by Judy Carman et al., titled, "A long-term toxicology study on pigs fed a combined genetically modified (GM) soy and GM maize diet." Can you ensure the health and safety of animals fed GMO-feed? The article is here: http://www.organic-systems.org/journal/81/8106.pdf

AExpert Answer

This response by Cami Ryan, research associate at the College of Agriculture and Bioresources at the University of Saskatchewan, addresses the study referenced in your question. An excerpt from the response is included below:

 

 

“From ‘I smell a rat‘ to ‘when pigs fly,’ bad science has been making the rounds of late. The multi-authored article 'A long-term toxicology study on pigs fed a combined genetically modified (GM) soy and GM maize diet' [referenced in the question] reports that pigs fed a diet of only genetically modified grain show a markedly higher incidence of stomach inflammation than pigs that ate conventional feed.

"However, it seems that—post-publication—the paper and its evidence fail the independent peer-review process on many fronts:

"David Tribe reviews the paper here: He says, ‘It’s what some call a fishing expedition in search of a finding, and a known pitfall of animal feeding trials on whole foods…’ Tribe points out (among other things) that some of the study’s observations might be attributed to compositional differences in the variety of soybeans or corn fed to the pigs: ‘[T]here is relatively little information in the paper about nutritional formulation, methods used for producing the pig diets, storage time for the grain and which particular varieties of grain were used in the diets.’

"Anastasia Bodnar expands upon this further in her Biofortified post 'Lack of care when choosing grains invalidates pig feeding study': ‘The authors aimed to do a real world study, with pig feed that can be found in real life. It intuitively seems right to just go get some grain from some farms. After all, that is what pigs eat, right? Unfortunately, it’s just not that simple…To hone in on any differences that may be caused by the GM traits, they would have to use feed with one or more GM traits and feed that doesn’t have the GM traits but that is otherwise as similar as possible. If the feeds aren’t very similar, then we can’t know if any differences in the animals is due to the GM traits or due to something else.’

"Dr. Robert Friendship (via Terry Daynard)—swine expert from the University of Guelph—points to methodological problems with ‘visual scoring’ and assessment of ‘inflammation’: '[I]t was incorrect for the researchers to conclude that one group had more stomach inflammation than the other group because the researchers did not examine stomach inflammation. They did a visual scoring of the color of the lining of the stomach of pigs at the abattoir and misinterpreted redness to indicate evidence of inflammation. It does not. They would have had to take a tissue sample and prepare histological slides and examine these samples for evidence of inflammatory response such as white blood cell infiltration and other changes to determine if there was inflammation.’

"Andrew Kniss clearly demonstrates the failings of the statistical analysis, poking holes in the study’s evidence. He states, ‘If I were to have analyzed these data, using the statistical techniques that I was taught were appropriate for the type of data, I would have concluded there was no statistical difference in stomach inflammation between the pigs fed the two different diets. To analyze these data the way the authors did makes it seem like they’re trying to find a difference, where none really exist.’”

If you have additional questions after reading this response, please ask.

Posted on December 7, 2017
The term “GMO” typically refers to crops or animals that, through genetic engineering, have had a gene (or a few genes) from a different species inserted into their genome. This is by design to improve a crop or animal with genetic engineering. In fact, me and my colleagues recently published a paper on this very topic that addresses this very topic and gives more details on the plant selection practices used for GE crops.   However, you pick up on something very... Read More
Answer:
Posted on December 7, 2017
Nearly all foods today have been genetically modified or altered in some way over thousands of years through selective breeding. However, there are only 10 commercially available GMO crops in the U.S: soybeans, corn (field and sweet), canola, cotton, alfalfa, sugar beets, summer squash, papaya, potatoes and apples.   Below is a table outlining what year the nine crops became commercially available:   Squash 1995 Cotton 1996... Read More
Posted on November 17, 2017
When people refer to Genetically Modified Organisms (GMOs), they are referring to precision plant breeding using genetic engineering. It allows plant breeders to take a desirable trait (like resistance to drought, insects, weeds, and disease) from one plant or organism and transfer it to the plant they want to improve, as well as make a change to an existing trait in a plant they are developing. You may have also heard of agricultural biotechnology or biotech seeds.... Read More
Answer: