From the American Medical Association to proposals in Congress, efforts continue to discourage the routine use of antimicrobials in food-producing animals.



A tug of war continues over the role of drugs fed to livestock as reports of human antibiotic resistance mounts.

No one doubts over-prescription of medications by physicians, often at the insistence of patients, is in part fueling the rise in bacterial resistance.

But the difficulty in explaining multiple resistance in an increasing number of pathogens is resulting in a renewed call for limits on routine use of antibiotics in livestock.

Most notable is the resolution passed recently by the American Medical Association (AMA) to phase out subtherapeutic use of antimicrobials in agriculture, points out Paul Sundberg, DVM, assistant vice president of veterinary issues for the National Pork Board. The AMA is also calling for a national program to combat antibiotic resistance and increased surveillance of antimicrobial use and resistance.

A bill to fund an interagency task force action plan on antimicrobial resistance was introduced in early May by Rep. Sherrod Brown (D-OH). HR 1771 looks at livestock use but also covers human use and education, says Leah Becker of the National Pork Producers Council, based in Washington, D.C. It has been included as an amendment to the fiscal year 2002 Agriculture Appropriations bill. To read the text of the legislation, log on to http://thomas.loc.gov/.

The concern over agriculture is that exposure to antibiotics in farm animals produces resistant foodborne bacteria that interferes with the ability of those antibiotics to treat human infections.

Livestock Antibiotic Use

In its resolution, the AMA contends 16 million lb., or 80% of all antibiotic use in agriculture, is at a constant, low level likely to produce antibiotic resistance.

For its part, the Animal Health Institute (AHI) painted a different picture. Richard Carnevale, DVM, AHI vice president of regulatory, scientific and international affairs, in a recent presentation reported on a 1999 antibiotic use survey. It showed 20.5 million lb. of antimicrobials were marketed for both food and companion animals. Of that total, 17.8 million lb. were used to prevent and treat disease, leaving 2.8 million lb. or 13% used as growth promoters.

Maybe even more telling, explains Carnevale, is the fact that only 24% of the total represents classes of antibiotics for both animals and humans. AHI contends that all such application in livestock production accounts for less than 5% of the total resistance problem. The full text of his talk can be found at www.ahi.org.

“There is a risk of antibiotic resistance any time you use antibiotics,” states Sundberg. That risk must be evaluated in terms of what good will come from removing them from the marketplace and what harm will come to the animals and to the producer, he says.

Sweden banned routine use of antibiotics in farm animals in 1986 without seeing any affect on human health. However, the ban has created growing problems in animal health, says Sundberg.

The Cost of a Ban

Discontinuing the use of antibiotics in hog production would “decrease feed efficiency, raise feed costs, reduce production and raise prices to consumers,” according to findings of a recent report of the Agriculture Department's Economic Research Service (ERS).

“This report helps put into perspective the debate on antimicrobial use in animals and confirms the value of antibiotics in promoting animal health,” states AHI President and CEO Alexander Mathews. “Antibiotics are important tools in the toolbox farmers use to keep animals healthy and to efficiently produce food. Consumers benefit from a safe, wholesome, abundant and more affordable food supply,” he adds.

The ERS report was based on recent studies of the economic impact of a hypothetical ban or partial ban on antibiotics. A ban on feed additives would result in losses of more than $45 million to hog producers, the report said.

The report, “Antimicrobial Drug Use and Veterinary Costs in U.S. Livestock Production,” can be viewed by logging on to www.ers.usda.gov/publications.

FDA's Antibiotic Plan

To deal with the growing threat of antibiotic resistance, the Food and Drug Administration (FDA) about two years ago proposed a new set of rules by which antibiotics will be approved for livestock. Sundberg says the agency is to be commended for the slow, scientific approach it is taking in formulating the final document.

The pork industry, in collaboration with the American Association of Swine Veterinarians, developed a list of judicious use guidelines last year to safeguard therapeutic use. This was developed as a pork safety fact sheet for producers. The fact sheet can be accessed at www.porkboard.org or requested by calling (515) 223-2600.

Antibiotic Alternatives

To give pork producers options to antibiotics, the National Pork Board formed an advisory committee to its Pork Safety Committee. The Non-Antimicrobial Production Enhancers group is made up of experts in the areas of probiotics, enzymes, acids and other growth-promoting products. Their charge is to figure out how producers can evaluate effectiveness of these products on their farms, explains Sundberg.

Early plans are to hold a symposium within a year to highlight the best information on use of subtherapeutic antibiotics and alternatives.




Quality Assurance Program Revised

In a way, the Pork Quality Assurance (PQA) program is returning to its roots. It started out as a single-level educational tool, expanded to three levels of participation and now is returning to a single-level, self-help program.

The effort remains strongly grounded as a pork checkoff-funded, food safety program, observes Paul Sundberg, DVM, National Pork Board and technical advisor to the program.

“Our vision is to keep the focus on using any animal health product correctly. We are not about to dilute the message of PQA that, for example, you must use antimicrobials correctly, follow correct withdrawal times and follow the advice of your veterinarian,” he stresses.

PQA began in 1989 as a single-level plan to prevent volatile drug residues in hogs. Over time, it expanded to a three-level program encompassing herd health strategies, medication withdrawal and animal care management strategies.

The revised manual, due out by early fall, will provide enhancements of those existing efforts in a single phase. The new publication builds on the 1997 PQA program.

It also will give producers a better explanation of what the Hazard Analysis and Critical Control Point (HACCP) program is, how it works and how it can serve as an example for practices on the farm, says Sundberg. HACCP is a food safety management system in which hazards are minimized and monitored based on performance.

PQA will have expanded sections on judicious use of antimicrobials plus information and standard operating procedures for needle use. Animal welfare information will be greatly expanded. Biosecurity, rodent control and swine health information that relates to food safety also will be bumped up, he notes.

“The bottom line of PQA is providing the producer with the ability to implement, economically, what it takes to stay in business,” says Sundberg. This program will help to fill the void for producers as they address their food safety programs, whether or not they are part of an organized marketing group.

A self-help checklist will be included to help producers gauge whether they are meeting the appropriate food safety standards, which may be requested by their packer or customers in a niche marketing program.

“Producers in the future will have multiple opportunities to market their products differently, whether it be related to animal welfare or drug use programs, and we hope the new PQA program will be a base from which they can launch those efforts,” he says.

PQA is coordinated by the National Pork Board and delivered by practicing swine veterinarians, university Extension and other agricultural educators, says Sundberg.

Producers who are current in their PQA education will use this new publication at the time of their re-certification, says Kristie Bray, PQA program manager, National Pork Board.
Joe Vansickle