Study Claims Short-Term Hay
Ration Would Reduce E. Coli

WASHINGTON — Researchers have discovered a simple way to dramatically reduce the risk of people getting sick from E. coli-tainted beef: Change the ration for a few days before cattle are slaughtered.

Feeding grain encourages the growth of E. coli bacteria that are strong enough to sicken humans, according to new Agriculture Department studies conducted at Cornell University.

But feeding hay instead of grain for a mere five days before cattle are slaughtered could virtually eliminate that risk, said USDA microbiologist James Russell, who did the study while stationed at Cornell.

"It's a way of attacking the problem long before the animal reaches the slaughterhouse, the meat reaches the supermarket or the meat is prepared by the consumer," Russell said. "We're very hopeful" the result will be far fewer sick Americans.

The study, in lastFriday's edition of the journal Science, is generating excitement among food-safety experts.

"This looks to be a relatively inexpensive, potentially important intervention that farmers can do," said Robert Buchanan of the Food and Drug Administration, lead scientist for the Clinton administration's food safety initiative.

The beef industry welcomed the news.

"We think it's a major breakthrough," said Gary Cowman, quality assurance chief for the National Cattlemen's Beef Association. "It's something very, very practical."

But there are still questions to be answered, he cautioned, including whether abruptly changing rations from starchy grain to fibrous hay overnight would cause digestive problems. Cowman said more research should settle those concerns within a year.

E. coli is a common bacterium that lives in the digestive tracts of humans and animals. Some E. coli strains sicken people; one strain — E. coli O157 — is highly toxic, causing bloody diarrhea and severe cramps and sometimes even kidney damage or death.

The Centers for Disease Control and Prevention estimate E. coli 0157 sickens up to 20,000 Americans each year, killing several hundred.

E. coli can get into beef during slaughter, from contamination with cattle feces. Thorough cooking, especially of hamburger, kills E. coli, but outbreaks from undercooked meat or poor kitchen sanitation increasingly make headlines. Just last year, E. coli prompted the nation's largest meat recall, 25 million pounds of ground beef.

Its ability to sicken depends on whether it is strong enough to survive the typical two hours that a person's meal sloshes around in the stomach's highly acidic juices. If so, the bacteria move down to infect the person's intestines.

Feeding grain increases acidity in the animal’s colon, where E. coli lurks. But no one had studied whether this cattle diet change let E. coli adapt to acidic conditions so it would pass unharmed through a human stomach.

First, Russell took fecal samples from Cornell cattle on different rations. Those fed more grain had more E. coli in their manure. In laboratory tests, those bacteria were less likely to be killed by stomach acid.

Next, he changed the ration. Cattle switched to a grain-based diet typical of commercial feedlots had a one million-fold increase in acid-resistant E. coli in their manure, Russell said.

Because of differences in how cattle digest starchy grains vs. roughage like hay, a hay diet doesn't increase their acid levels. Thus, Russell found that cattle fed hay had E. coli that was easily destroyed in an acid bath similar to the human stomach.

None of Cornell's cattle actually harbored the super-toxic E. coli O157, just milder strains. So Russell tested that superbug in the laboratory, and found that E. coli O157 becomes resistant to stomach acid just like other E. coli strains. But to be sure, FDA's Buchanan cautions that the hay diet should be tested in cattle actually infected with the super-bacteria.

Some cattle feeders say they have doubts about the research, but they are willing to change their operations if it will make beef safer.

"Anything we can do to produce a safer product, I'm willing to do," said Jim Miller, who operates a feedlot near La Salle, Colo.

"If that's the case, I'll have a truck of ground hay going down my feed alleys in an instant," Miller said.

Dick Farr, president of Farr Feeders, also said he was skeptical about the report.

"I’d like to read the research," he said. "But, it sure would be easy to try."

Farr said the final ration for cattle fed at that lot is already 10 percent hay, and changing to a diet of all hay wouldn't make that much difference because E. coli grows in the animal's manure.

"I don't think changing the diet that late would change that, but if it works, we'll do it," Farr said.

Dan Webster at Webster Feedlot agrees.

"I'm scratching my head trying to figure out how changing the diet just five days before slaughter would change things. But if it works, I'm there," he said.