Ethanol plants and livestock producers have created a symbiotic relationship.
Ethanol plants and livestock producers have created a symbiotic relationship. Cattle producers feed their livestock distiller’s grains, a by-product of the ethanol distilling process, giving ethanol producers an added source of income. But recent research at Kansas State University has found that cattle fed distiller’s grain have an increased prevalence of E. Coli 0157:H7 in the hindgut. This particular type of E. Coli is present in healthy cattle but poses a health risk to humans who can acquire it through undercooked meat, raw dairy products and produce contaminated with cattle manure.
“Distiller’s grain is a good animal feed,” says Dr. T.G. Nagaraja, a professor of diagnostic medicine and pathobiology at Kansas State’s College of Veterinary Medicine. “That’s why ethanol plants are often built next to feed lots.” The growth in ethanol plants means more cattle are likely to be fed distiller’s grain, therefore harboring 0157:H7 and potentially a source of health risk to humans, Dr. Nagaraja says. That is why he and Dr. Jim Drouillard, a Kansas State professor of animal sciences, have been collaborating on testing distiller’s grain-fed cattle for 0157:H7.
Through three rounds of testing, Dr. Nagaraja said the prevalence of 0157:H7 was about twice as high in cattle fed distiller’s grain compared with those cattle that were on a diet lacking the ethanol by-product. “This is a very interesting observation and is likely to have profound implications in food safety,” Dr. Nagaraja says, adding that research in the next few years will focus on finding out why 0157:H7 is more prevalent in cattle fed a distiller’s grain diet. He says it could be something that changes in the animals’ hindgut as a result of feeding distiller’s grains, or maybe the by-product provides a nutrient for the bacteria.
“Feeding cattle distiller’s grain is a big economic advantage for ethanol plants,” Dr. Nagaraja says. “We realize we can’t tell cattle producers, ‘Don’t feed distiller’s grain’. What we want to do is not only understand the reasons why 0157:H7 increases, but also find a way to prevent that from happening.”
