With wet distillers grain becoming ever more available as a feed source due to the government subsidized ethanol industry, it’s not good news that they might be increasing levels of dangerous E. coli O157:H7 in cattle hides and manure. A primary co-product of the ethanol production process, distillers grains are the product remaining after the ethanol is removed from the fermented corn mash.
But studies by USDA’s Agricultural Research Service in Clay Center, NE are showing a connection between feeding wet distillers grains and E. coli levels in cattle.
Distillers grains are a cereal byproduct of the distillation process, and traditionally were only available as fodder for livestock to those who happened to be near a brewery. But since the massive ethanol boom, corn-based distillers grains have become a high protein livestock feed that are readily available thoughout the country.
James Wells, the USDA microbiologist at the Nebraska research station, says his research is finding that E. coli pathogens live longer in feces from cattle fed with more wet distillers grain. The research, underway since 2007, first involved 603 steers that were put on different diets. A follow-up study was conducted using market heifers.
The heifers were put on three diets: no wet distillers grains, 40 percent distillers grains and 70 percent distillers grains. Wells said researchers wanted to see if they could change the shedding of the pathogen in the feces and hides. He said changing the amounts before the heifers were taken to slaughter reduced the pathogen levels, but it took longer than 28 days to achieve.
The USDA research project also found that E. coli O157:H7 in the feces of the cattle died more rapidly in animals that were fed corn. Wells said high-moisture or dry-rolled corn contains starch that is not digested and excreted in the feces. There is less starch in feces of cattle fed wet distillers grains and that may help explain why E. coli is present at higher levels.
Wells says distiller grains are a good feed source for producers, and the goal of the Nebraska research is find out what component might be affecting E. coli levels. He says sulfur, nitrogen and fat are all present in greater amounts in distillers grains than in corn, and any one of these might be the one component causing the spiked levels.© Food Safety News