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Prudent Use of Antibiotics

by Clint Peck, Director of Beef Quality Assurance, Montana State University

The warning is stern and clear.

“If we’re not careful with antibiotics and the programs to administer them, we’re going to be in a post antibiotic era,” said Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention earlier this year.

And make no mistake, the movement to eliminate antibiotics in agriculture is advancing. The World Health Organization said surging antibiotic resistance is one of the leading threats to global human health – and the White House last month said the problem is “urgent.”
Johns Hopkins University health sciences professor Ellen Silbergeld said there’s no doubt drug use in farm animals is a “major driver of antimicrobial resistance worldwide.”

However, a priority for all cattle producers is the well-being of their animals. Antibiotics and antimicrobials are widely recognized as an important and necessary tool in protecting animal health.

Keeping Animals Healthy

Beef Quality Assurance (BQA) programs support science-based decisions regarding the safety and efficacy of antibiotics and antimicrobials used in animal agriculture. Several layers of protection have been put in place to ensure antibiotics are used to keep animals healthy without harm to public health.
Deviation from label inclusions could potentially cause lack of effectiveness for the disease being treated, toxicity to the animals, or a violative residue in food harvested from the animal. A veterinary client patient relationship (VCPR) is the first step in making sure that all livestock health products are used appropriately.

One aspect of a VCPR is extra label drug use (ELDU). Federal law enables veterinarians to adjust the label use of an approved drug when the health and well-being of that animal or group of animals is threatened. But, ELDU cannot be considered if the purpose is for growth promotion, reproductive performance, or alteration of cost of therapy.

There’s one very important point in the law, even if the rationale for ELDU is reasonable – ELDU must not lead to a violative drug residue.
In the case of penicillin, for example, only a veterinarian can make the decision that the appropriate dose is more than the dose label; and the veterinarian must add a prescription label to the drug. When this altered dose is used, the necessary withdrawal time must be changed from the withdrawal time on the label by the prescribing veterinarian.

If there is not sufficient information to establish this slaughter withdrawal time, then the animal may not enter the food chain.

ELDU and Feed Additives

The laws and rules are different for injectable drugs and drugs administered in the feed. Not even a veterinarian may legally prescribe or use drugs in feed in an extra-label manner. Also, feeding rations containing non-approved combinations of drugs is illegal.

This means that concurrent feeding of drugs not approved to be fed together violates federal regulations. Label directions on feed additives must be followed exactly, including for example disease indication, drug concentration in the feed, frequency and duration of administration, and withdrawal times.
BQA Producer Guidelines for Judicious Use of Antimicrobials, which have been in place since 1987. The guidelines specifically outline the appropriate use of antibiotics:

BQA programs stress that starting at the cow-calf level all cattle producers have an ethical responsibility to use antibiotics in such a manner that the animals they raise do not carry residues that violate FDA standards.

For more information, the following paper can be found at this link, “Using FDA Approved Medications: Common Scenarios” by Mike Apley, College of Veterinary Medicine, Kansas State University; Virginia Fajt, Texas A&M University and Chair of the Committee on Pharmaceutical and Biologic Issues of the American Association of Bovine Practitioners; and Dee Griffin, University of Nebraska – Lincoln, Great Plains Veterinary Educational Center.