Judicious Use of Antibiotics

Judicious Use of Antibiotics

The recent changes regarding antibiotic use in food animals have taken effect, January 1, 2017. The reasons and rules are defined by the United States Food and Drug Administration (FDA) in two major documents. The first, The Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals(Guidance for Industry #209) defines the framework, collaboration efforts and strategies proposed to reduce the incidence of antimicrobial resistance. On January 3, 2017 the FDA also announced the implementation of New Animal Drugs and New Animal Drug Combination Products Administered in or on Medicated Feed or Drinking Water of Food-Producing Animals (Guidance for Industry #213). This document defines the use of antimicrobial drugs that we feed to food producing animals. Specifically, antibiotics that are important in human medicine. The following is an excerpt from the FDA’s Judicial Use of Antibiotics. 

“Antimicrobial drugs have been widely used in veterinary medicine for more than 50 years. When used judiciously, antimicrobials can effectively fight infections and improve animal health. However, overuse of antimicrobials promotes the development of antimicrobial-resistant bacteria. Today, antimicrobial resistance is a worldwide phenomenon and growing problem. To slow the emergence of resistance and extend the useful life of antimicrobials, stewardship of antimicrobials in both human health and veterinary settings is essential.”

Under their first principle, the FDA considers antibiotics associated with the treatment, control, and prevention of specific diseases to be “therapeutic uses” that are necessary for assuring the health of food-producing animals. “Therapeutic use” includes the following three categories: to treat an animal with an illness, to control the spread of illness in a herd, and to prevent an illness in healthy animals when disease exposure is likely.

The Judicious Use of Antibiotics goes on to define “production uses” of antibiotics as being expressly indicated and used for enhancing the production of animal-derived products. The FDA believes that “production use” indications such as “increased rate of weight gain” or “improved feed efficiency” are no longer appropriate (violating their principles) reasons to use a medically important antibiotic. Therefore, antibiotics can no longer be used in this manner. This removes any antibiotic drug label claim for increased rate of gain or improved feed efficiency from the livestock feed market.

Principle two introduces the expanded implementation of “veterinary oversight” and consultation with use of the Veterinary Feed Directive (VFD). I am calling this layer “expanded” because we have been using VFDs in a much smaller scope for a decade on swine and beef operations. Now, ALL of the medications that are fed to the major species of food producing animals have moved to require a VFD. The “major” food animal species are defined by the FDA as cattle, swine, chickens, and turkeys. At some point in the future, medicated feed drugs for minor species are expected to convert to requiring a VFD as well (e.g., oxytetracycline in honey bees). One VFD drug is already approved for use in minor species (e.g., florfenicol in fish).

In order to minimize the development of antimicrobial resistance, the FDA believes that it is important to ensure the judicious use of medically important antimicrobial drugs in animal agriculture. The FDA has put new limits on medically important antimicrobial drugs that are considered necessary for treatment. The new regulations and veterinary involvement are meant to reduce overall use of medically important antimicrobial drugs, thereby reducing antimicrobial resistance. It is the intention of the FDA to still maintain the availability of these drugs for appropriate use in animal agriculture.

About the Author
Dr. Colleen Lewis is a 1996 graduate of Kansas State University, College of Veterinary Medicine. Her career has taken her to many places as a practice owner, consultant, embryologist, and mentor. She enjoys mixed animal practice, teaching, traveling, farming and high school sports with her husband, Andrew and their three boys.