The Veterinary Feed Directive: Questions and answers for Oregon livestock producers

Oregon livestock producers must comply with federal law regarding the use of feed-grade antibiotics in their operations. FDA guidelines promote the judicious use of medically important antimicrobial drugs in food animals and reduce the overuse of antibiotics in livestock populations. The law helps reduce the likelihood of increased bacterial resistance to antibiotics while maintaining a safe domestic food supply.

The law affects producers or caretakers of important livestock species (such as cattle, swine, poultry and sheep) and the veterinary profession. Since the 1940s, livestock producers have used feed-grade antibiotics not only to prevent, control or treat infections caused by bacteria, but also to promote growth and efficiency in animals.

Beginning in 2017, certain antibiotics administered via feed and water could only be used under the supervision of a veterinarian. Livestock producers must obtain a Veterinary Feed Directive signed by a veterinarian before purchasing medically important feed-grade antibiotics. Antibiotics added to water for food animal consumption also require a veterinary prescription. The law also removes growth promotion and efficiency claims on feed labels because the FDA no longer recognizes these claims as a legitimate use of antibiotics (Figure 1).

What is a veterinary feed directive for medicated feed?

A VFD for medicated feed is a statement in writing, issued by a licensed veterinarian in the course of the veterinarian’s professional practice, that authorizes the use of a VFD drug or combination VFD drug in or on animal feed. A VFD is similar to a prescription written by a medical doctor: the attending veterinarian writes a VFD to treat a specific disease or illness that he or she has diagnosed while working with the operation. The VFD authorizes the livestock producer or caretaker to purchase feed-grade antibiotics to treat specific animals, with the restriction that the drug must be used in accordance with the label as well as with the conditions for use approved, conditionally approved, or indexed by the FDA. Under the VFD rule, medically important, feed-grade antibiotics require a VFD and can no longer be made available over the counter.

What is a veterinary-client-patient relationship?

Within Oregon, a veterinary-client-patient relationship is the foundation of the livestock health care system. The VCPR exists when the veterinarian has:

• Sufficient knowledge of an animal to initiate treatment based at least on a general or preliminary diagnosis of the animal’s medical condition.
• Seen the animal within the last year and is personally acquainted with the animal’s care by virtue of a physical examination or by medically appropriate and timely visits to the premises where the animal is kept.

It is imperative that a veterinarian assumes the responsibility for making medical judgments regarding the health of an animal and the need for medical treatment. It is equally important that the client (the owner or caretaker of the animal or animals) has agreed to follow the instructions of the veterinarian. The practicing veterinarian also must be readily available for follow-up in case of adverse reactions or failure of the therapy regimen.

Which medications are affected?

The VFD rule affects medications that are important in human and livestock healthcare. Table 1 highlights the human-animal medications affected by the regulations and animal-only medications that are not affected. Products that are not medically important, such as ionophores or bacitracin, may be used without a VFD. Furthermore, the label on medications not requiring a VFD may continue to promote feed efficiency and growth enhancement because there is no evidence that the bacterial populations treated are remotely related to human health. However, medically important products, such as feed-grade forms of penicillin and tetracycline, must be purchased with a VFD, and the labels on these products may not claim improved feed efficiency or enhanced growth — only prevention, control or treatment of specific infectious conditions.

On a practical basis, a producer must be careful to use a VFD antibiotic consistent with the product label. Be aware that each company has its own specific label-approved antibiotic as well as combinations of antibiotics and other feed additive compounds. Do not substitute a drug from one manufacturer for another manufacturer’s equivalent drug unless the labels are identical in terms of approved drug combinations. For example, at this time generic chlortetracycline cannot be fed in combination with Bovatec®, but Aureomycin®, which contains chlortetracycline, is approved for feeding in combination with Bovatec®.