Skip to content

An antidote in time


Le Center, Minn. — Microbiologist Peter Nash has always been ahead of his time. During the Gulf War, he worked on anthrax tests, but when the war ended, so did the federal funds. In the late 1980s, he developed quick swab tests to detect Listeria in feedlots and E. coli in processing plants. But the livestock industry didn’t have a sense of urgency or financial incentive to invest in testing.

Outbreaks and threats have changed all that. But by the time public policy and markets caught up to his research, Nash was on to something else.

Now, after nearly three decades of microbial study, the president of Camas Inc. has designed all-natural cattle feed additives to inhibit a dangerous E. coli 1057:H7 strain and improve feed efficiency with “impressive results.”

What’s kept him going? “The dream that eventually we would hit it right,” Nash says.

Forming an attachment

In its Le Center labs, Camas formulated two nutritional additives to mix with feed. Both are delivered as coatings on soy-based pellets produced by Honeymead in Mankato. The pellets are coated at Camas’ pilot plant. In a cow’s stomach, the additives swell up and release material that coats the lining “like pepto bismal,” Nash says.

“This delivery mechanism is a breakthrough,” says Brad Mitteness, Camas’ marketing director. “No one has ever done it before.”

One additive attaches to E. coli 0157:H7 and stops it from colonizing; the other targets “bad” bacteria that compete with good bacteria in a cow’s digestive system. The net effect is it takes less feed to effect weight gain. Camas is coating pellets with one or both nutritional additives, although the E. coli treatment is only needed for 30 days before slaughter — an ounce or two per day.

Camas has not yet priced its digestive additive, but Nash says it will cost considerably less than its value. “Farmers can start feeding this to cattle at a young age and it will more than pay for itself.”

So early so often

Fighting bugs in livestock was not what Nash envisioned when, as a young man, he studied to be a medical doctor and expected to treat human patients. After obtaining his Ph.D. in microbiology, he taught for 20 years at the Indiana School of Medicine, University of Minnesota and Minnesota State University, Mankato – covering 13 areas of medicine, from parasitology to immunology to virology.

In 1984, Nash received a call from BSI, an emerging medical company (now called Surmodics) specializing in human diagnostics. Relocating to Eden Prairie, he went to work developing tests for strep, whooping cough, salmonella, toxins and other diagnostics.

Along with BSI founders Don Robinson and John Rosevear, an M.D. and researcher, Nash spun off Camas Inc. in 1987. From the University Technical Center in Minneapolis, they expanded their work in rapid human diagnostics to agriculture — researching Campylobacter, Pasteurella and E. coli 0157:H7 with federal dollars. Camas has done work for the Department of Defense, U.S. Marines and USDA.

In 1989, with AURI’s help, Camas designed a state-of-the-art field test for Listeria, a bacterium that causes serious illness or death in people with weak immune systems. Carried in contaminated soil or water, “it’s a sanitation issue,” says AURI meat scientist and food safety expert Darrell Bartholomew. “It can get on floors, ceilings, even in refrigeration. And once it’s established, it can cause problems.”

“The test kit was successful but, at that point, companies preferred not to test. They didn’t want to know whether they had a problem or not.” Now they do, Bartholomew says, because “a couple years ago we had some huge recalls with Listeria in ready-to-eat foods. There were some deaths and millions of pounds of product were recalled.”

Camas also developed and patented a swab test for E. coli 0157:H7 that showed results in a few minutes. But Nash says USDA didn’t want to test processors until it had a procedure to deal with contaminated meat. “They said, ‘if you have it, what do you do with it? And if you have 600 carcasses coming down the line, you can’t stop the line.’ … We couldn’t get investors. Nobody seemed to be too excited about 0157:H7.”

Then there was a major outbreak in 1993 and tests were mandated a few years later. But like the Listeria and anthrax tests, Camas had already abandoned the project. “They were ahead of their time,” Bartholomew says. “They came out too early.”

Treatment vs. testing

After the government funds for anthrax tests dried up, Camas tried developing other diagnostics, but were discouraged. “Doctors don’t want the tests on the market. They’re afraid people would misuse and misrepresent the results. Was the sample taken right? Were the results read right? They can’t be perfect.”

Switching from diagnostics to treatment, Nash and Rosevear began exploring the potential of an isolated protein that clung only to E. coli 0157:H7. Not only did it detect the bacteria’s presence, but they also discovered it would prevent the E. coli strain from adhering to the intestinal wall. “If it can’t adhere, it can’t reproduce and it’s flushed out of the digestive tract,” Mitteness says. None of the additive enters the bloodstream.

There are hundreds of strains of E. coli; most are benign. However, the 0157:H7 strain has evolved into a potent, deadly toxin-producing bacterium that can shut down kidneys and cause death. Nash says the only treatment is support therapy — keeping a patient stricken with diarrhea hydrated, for example.

E. coli is a tough opponent, Nash says. “0157:H7 likes cold weather, it will thrive in the refrigerator, and is detrimental to young kids and the elderly.” The bacterium is primarily carried in the feces of cattle and can get into “meat, produce, water — anything that comes into contact with manure from affected cattle.” Contamination usually occurs at the processing plant — typically in ground hamburger, although cooking meat well will kill the bacteria.

“E. coli (in processing plants) is at such low levels that finding it is like looking for a needle in a haystack,” Bartholomew says. “You can test and test and test. What I like about what they’re working on is it will eliminate E. coli at the farm level.”

Revolution at the right time?

In the early 1990s, when Nash and Rosevear discovered they could stop 0157:H7 without drugs or antibiotics, they knew the research had huge implications. But they were again skeptical that the industry would invest in it.

Nash left Camas in 1994 to do consulting work for a Madison, Wisc. company. After Rosevear died in 1998, Nash returned to pursue treatment-oriented feed additives. Around the same time, Steve Weiland, who holds a master’s degree in microbiology and immunology, joined Camas. Mitteness had joined in 1997.

They experimented with several isolated proteins to target bugs competing with good bacteria in a bovine’s first stomach chamber, or rumen. When cattle eat grass, the rumen breaks down cellulose into protein and carbohydrates. “But some bacteria in the rumen are not helpful; they break up protein into ammonia and waste protein,” Mitteness says. The Camas additive “bathes the gastrointestinal tract so the targeted organisms can’t attach to stomach lining and reproduce — they just float right on by. … It’s an all-natural product. You can’t overdose”

Replicated trials have been conducted on hundreds of cattle in Minnesota and Idaho and the results “have been startling,” Mitteness says. “We are not sure why, but beside gaining weight faster, the cattle also grade and yield better.” In one trial, treated cattle yielded 80 percent choice and prime meat, versus 67 percent in the control group. The USDA quality grade is based on intramuscular fat content, which gives meat tenderness and flavor, as well as the animal’s age. “That’s a huge economic boost for cattle farmers operating on thin margins,” Mitteness says.

“All of the farmers who have helped in the trials have been positive,” Nash says. “I’ve never experimented with new products before where the people who tested it are so excited about it.”

If safety sells …

Last spring, to get closer to their feedlot trials and their Mankato supplies, Camas moved to Le Center where there was an available building and “a lot of local support,” Nash says. In November, the company started limited production runs and expects to be in the market within 12 to 18 months, selling to feed companies and producers, including natural beef farmers because “it doesn’t impact natural or organic labels,” Mitteness says.

In addition to the cattle additives, the company is designing products for hogs and poultry and plans to roll out 10 new products over the next few years. The staff of 13 should double within a year, Mitteness says.

Nash says the time is right because “antibiotics are going out of favor. The European Union is banning many antibiotics. Also, we can feed treatment in cases where you can’t give antibiotics (such as lactating dairy cattle).”

The technology has numerous other applications. For example, “steers pushed to gain weight in a feedlot will suffer with low rumen pH. We can remove those acid-producing bacteria,” Mitteness says. “We can find the bug we want to target, grow it in the lab, figure out its adherence mechanism, then engineer a product that blocks that specific strain.”

Adding value to cattle by promoting weight gain is a direct economic benefit, but Bartholomew says a safe food supply has economic value too. “Food safety is difficult to put a dollar value on, but when people stop consuming (because of an outbreak) that has real impact. Processors can maintain separate identities for this meat and if it’s staying raw, they have a safer source. I can see a demand building for animals that are treated by this process.”

“It’s something that can have national impact — and beyond. It has real potential and we hope it will be applied.”