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Wednesday January 17, 2018

Is corn feeding causing E. coli?

The recent deadly E.coli outbreak in Germany has breathed new life into the Internet amateur food scientists’ claim that “factory farming” of beef cattle is causing the epidemic. More specifically, the “unnatural” practice of feeding corn to cattle corn is causing the outbreak. The cure, then, according to those like Modern Serenity blogger Nick Andre, is simple: “The solution is ultimately to favor a grass-fed, pasture raised model of raising cattle rather than a feedlot based operation.”

But would such a system-wide change really affect the amount and severity of E. coli in the food system? Nebraska U.S. Department of Agriculture microbiologists Elaine Berry and James Wells, who are headquartered at Clay Center, reviewed more than 280 existing scientific studies on the subject last year for a book chapter in Advances in Food and Nutrition Research. Here’s what we know—and don’t know—based on the best of the research:

  • The Nebraska researchers caution that the potential effects of what cattle eat on how much and how often they shed the dangerous form of E. coli, O157:H7, must be deduced by looking at the overall large body of research, not from any single study. However, that’s the mistake pasture-feeding advocates often make by relying on a single study from 1998 that involved only three cows. In that study, cattle fed a ration made up of corn and ground soybeans, typical of what most cattle feedlots use, had higher total E. coli populations than cattle fed only hay. When the grain-fed cattle were abruptly switched to hay, the number of E. coli in their manure dropped by a thousand times, and the number that could pass through the acidic environment of the human stomach and thus posed a higher threat of illness declined by 100,000 times. However, what’s important to bear in mind about the study is this: No E. coli O157:H7 were detected, in any of the animals. The authors merely assumed the dangerous 0157:H7 strain would behave similarly to the generic E. coli they found. We know, based on research since, that’s not necessarily true.
  • When you do look at that larger body of research, it does seem that more E. coli, including the dangerous 0157:H7, does appear in the manure of cattle fed grain diets than those fed forage diets. But the conclusions of the numerous studies on the effect of switching to hay are often contradictory and far from clear, including studies showing cattle purposely infected with E. coli O157:H7 were potentially infective to cattle around them for more than ten times longer when fed hay than when fed corn. The bottom line is we know we can change the amount and severity of E. coli by changing the diet of cattle, but we don’t always know why, nor how to repeat it consistently. We do know feeding a grass-based diet is certainly no silver bullet.
  • The review demonstrates another thing we know to be true of E. coli O157:H7: It is naturally carried by animals never fed corn-based feedlot diets, including both tame and wild deer, rabbits, raccoons, opossums, rats, pigeons, gulls, rooks, starlings, and numerous other species of birds.

Corn and chopped corn plants (silage) are an important part of producing cattle to the quality level your customers demand, and they have been for more than a century. As any farmer who has had the unfortunate experience of leaving the gate to a corn field open around a group of cattle can tell you, cattle enjoy corn, whether or not they evolved to eat it. Cattle benefit from the nutritional profile of corn, when they are fed in the controlled environment of a feedlot that are almost always under the care of a professional nutritionist, and consumers benefit from the efficiency corn and soybean based cattle feeds bring by their lower beef prices.

What are your thoughts? Leave a comment by clicking the link below. 

As you court the green movement's call for more "local, sustainable" farming, it's important to be completely clear about some of the movement's underlying assumptions.

When Bill Weida, a retired Colorado College professor of economics, spoke before the 2011 Nebraska Environmental Action Coalition meeting in Lincoln on April 30, he repeated a piece of conventional wisdom that should tip off grocers to the underlying philosophy of today's "local and sustainable" farming movement. 

“...consumers are willing to pay more for better food," Weida told the Lincoln audience, "[but] it costs more for traditional agricultural products because it’s a closed system: farmers are doing all the production, processing, and marketing.... Right now, the land and production skills for sustainable agriculture still exist, but what’s missing is the processing and marketing.”

Weida, a former director of the Food and Water Watch's Global Resource Action Center for the Environment's Factory Farm Project, travels the country presenting his economic case that the current food system as we know it is broken and unsustainable. Because industrial farmers (that is, the larger farms that today raise the majority of our food and fiber) keep on producing even when markets are down -- unlike traditional small farms that either cut back on cropping and livestock or went bust in response to market declines. The result, Weida argues, is a system that is chasing unsustainable levels of production, a system that must return wholecloth to the traditional small-farm system in which farmers not only raise food for their communities, but they process it, deliver it and market it themselves, as well.

Weibe isn't alone in that sentiment. Locally raised is a double-edged sword that may actually work against the community grocer. Why?

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