It seems feed additives are under fire the world over. New concerns over antibiotic resistance put feed medications at risk.

Fifteen years ago Sweden, now just recently Denmark, banned subtherapeutic (routine) use of feed additives for growth promotion. Use of several feedgrade medications have been suspended in the European Union, citing the "precautionary principle." The principle calls for taking precautionary steps regardless of scientific basis.

In the U.S., HR 3266 authored by Rep. Sherrod Brown (D-OH), calls for banning antibiotics used for growth promotion in livestock unless it can be shown that their subtherapeutic use does not result in antibiotic resistance and a threat to human health.

A sweeping plan has been proposed by the Food and Drug Administration (FDA) to provide a framework to evaluate existing and new feed additives or antimicrobials for their contribution to antibiotic resistance and potential effect on public health.

In the view of one industry observer, the plan could do more harm than good if implemented as is.

"FDA's stance is that we need this framework so the drug companies understand what the rules are about approving drugs, while taking into account antibiotic resistance, and that the companies can play by the rules," explains Paul Sundberg, DVM, assistant vice president, Veterinary Issues, National Pork Producers Council (NPPC).

The concept is sound. But he warns the way the FDA proposal is written could have dire, unintended consequences.

"It will severely limit the availability of antimicrobials to animal agriculture, both new and previously approved products," he says.

Comments Sundberg: "You'd think restricting the use of antimicrobials would decrease antibiotic resistance and therefore increase food safety. But it could have the"1/20/2000 12:10:03 PM","Inbound","","","1426","Re: Rookie pics" opposite effect."

It's possible we could be marketing animals that aren't as healthy, posing a greater food safety risk, he suggests. The potential for antibiotic-resistant bacteria could even be heightened because producers and veterinarians would be forced to rely on a narrow supply of products.

The Real Issue But according to Sundberg, the real issue in the debate over feed additives is not whether bacteria become resistant. They do that in order to survive, whether in the environment or after antibiotics are used. The real issue is whether human treatment is compromised due to antibiotic susceptibility changes occurring in the bacteria.

"If treatment is compromised, and that is due to antimicrobial use, in livestock or in humans, then you have a situation you have to address," he admits.

But not a single case of human treatment failure due to agricultural antibiotic use has been documented, stresses Sundberg. And some of the antibiotics like tetracycline, penicillin and tylosin have been used safely for more than 40 years.

One way you fight antibiotic resistance is to maintain a number of different products at your disposal, he says. Rotating products for maximum effectiveness and avoiding antibiotic resistance is one procedure that is followed in human medicine and hospitals, points out Sundberg.

The problem for pork producers and their veterinarians is there aren't enough approved products to go around. And Sundberg says the future doesn't look bright.

Drug companies are questioning the sense of targeting research and development funds to produce antibiotics for animal use due to the clamor over antibiotic resistance and the potential for further product restrictions.

As a result, there may be quite a decrease in the availability of antibiotics for use in farm animals in the next 10 years, says Sundberg.

On the bright side, pharmaceutical firms are making a major research investment into new, novel ways to kill bacteria without resistance occurring.

The industry is also taking some positive steps in dealing with the antibiotic resistance issue, says Sundberg.

The American Veterinary Medical Association (AVMA) and the American Association of Swine Practitioners produced judicious use guidelines. Educational materials are being developed to distribute to veterinarians by AVMA using a grant from the FDA.

NPPC is adapting those guidelines to provide similar educational materials to pork producers, using an FDA grant and producer checkoff funds, says Sundberg. The goal is to make producers partners in ensuring safe and proper use of antimicrobials.

In the spring, NPPC will roll out a revised version of Pork Quality Assurance Program Level III. Revisions will include more information on judicious drug use and antibiotic resistance.

Sundberg stresses both veterinarians and producers need to be aware of judicious use guidelines. Two main keys are obtaining a proper diagnosis and following label or veterinarian instructions.

Swedish Model Iowa State and Oklahoma State economists have been awarded NPPC checkoff-funded research grants, in cooperation with the National Pork Board, to look at the economic effects of implementing the Swedish Model of drug use in the U.S.

One of the main concerns with implementing the Swedish Model is the wide differences between traditional Swedish and mainstream U.S. pork production.

In short, Swedish production involves farrow-to-finish operations, averaging about 50 sows, that are required to follow strict animal welfare and drug use guidelines. Although using antibiotics for growth promotion isn't allowed, they can be used in feed therapeutically. That means they are used at high levels, short term.

The 1985 ban on use in Sweden was done in response to consumers, particularly housewives, questioning the safety of their meat supply. The farmers asked the government to limit use of certain antibiotics and the government responded by banning the subtherapeutic use of all feed antimicrobials, says Sundberg.

Sweden has a very controlled system, he says. Veterinarians work in concert with government in dispensing medications and monitoring drug use.

In response to interest in the Swedish Model of using antibiotics, Sundberg and a contingent of pork producers visited northern Europe last year.