Antibiotics that are medically important to people will soon be off-limits for growth promotion in livestock. And after Jan. 1, DVMs will decide what's medically necessary in animal feeds and what's not.
In this new era, it's more important than ever that veterinarians stop and review the laws governing their livestock practice. (Photo Getty Images)In the United States we enjoy one of the safest and most affordable food supplies in the world, thanks to years of hard work by farmers, ranchers, veterinarians, processors, packers, distributors, government agencies-and the list goes on. So that we can continue this privilege, it's the responsibility of both veterinarians and livestock producers to understand and follow the laws and be prepared to meet new standards in the years to come.
The U.S. Food and Drug Administration (FDA) is responsible for protecting public health by ensuring the safety, efficacy and security of human and animal drugs and the food supply, among other things. All antibiotics available for use in livestock-whether over the counter (OTC), prescription or through a veterinary feed directive (VFD)-are used under FDA guidance and regulation.
Depending on the product label, OTC and prescription products can be administered in feed, in water or by injection. While the first two categories have been around for many years, the VFD option is a fairly recent one in livestock production. It was established as part of the Animal Drug Availability Act (ADAA), passed by Congress in 1996, to regulate the distribution of certain animal drugs in or on animal feed. Examples of new animal drugs approved with a VFD label are florfenicol use in fish and tilmicosin for use in swine and cattle.
So why do we need more regulation on the use of medicated feed products? There has been a growing concern that the use of antibiotics in veterinary medicine, specifically those used in food animals, are contributing to antibiotic resistance in people. An FDA report released in December 2015 states that most antimicrobial drugs approved for use in food animals are marketed for use in feed (74 percent) or water (22 percent). Furthermore, the report indicates that 97 percent of these drugs are dispensed OTC, or without veterinary supervision.
FDA actions on antimicrobials in food-producing animals
> Animal Drug Availability Act (ADAA) (1996), establishing the Veterinary Feed Directive (VFD) designation for certain medicated feed products
> GFI No. 152 (2003), defining medically important antimicrobials
> GFI No. 209 (2010), outlining the FDA's position on judicious use and veterinary oversight of medicated feed products
> GFI No. 213 (2013), providing mechanisms for industry to comply with the VFD ruling and withdraw all growth promotion claims
> Veterinary Feed Directive: Final Rule (2015), updating the VFD rule and changing medically important OTC medicated feeds to VFD status
Given the concern over antibiotic resistance, recent regulations have proposed phasing out the use of medically important antibiotics in food animals for production purposes and to ensure that licensed veterinarians oversee other uses of these drugs. (See "FDA actions on antimicrobials in food-producing animals" at right).
Here's a rundown:
1. In 2003, the FDA published the Guidance for Industry (GFI) No. 152, which designated antimicrobials used in food animal species according to their importance in human medicine.
2. In 2010, GFI No. 209 established two voluntary principles for the use of medically important antibiotics in the feed or water for food-producing animals: (1) Limit to uses considered necessary for assuring animal health (as opposed to growth promotion), and (2) include veterinary oversight or consultation for those uses.
3. GFI No. 213, published in 2013, outlined procedures whereby makers of medically important antibiotics could voluntarily change their medicated feed labels to phase out claims for growth promotion and establish indications for therapeutic use in foodproducing animals.
4. GFI No. 213 was released as a final ruling in June 2015, and it becomes effective Jan. 1, 2017.
Here are the important changes taking effect from GFI No. 213:
> No more antibiotics for growth promotion. The use of medications in feed considered “medically important” in human medicine will be restricted to the treatment, control or prevention of bacterial diseases of animals, under the oversight of a veterinarian. This removes the growth promotion, feed efficiency and milk production uses from the labels of all currently approved medically important drugs used in feed.
Drugs moving from OTC to VFD on Jan. 1, 2017*
In order to further protect these antibiotics' use in people, the FDA has switched these livestock antibiotics from OTC to Veterinary Feed Directive status, requiring veterinary oversight to ensure they're "medically necessary":
> chlortetracycline (Aureomycin, CTC, CTC. Chloratet, ChlorMax, Chlortetracycline, Pennchlor, Deracin)
> chlortetracycline/sulfamethazine (Aureo S, Aureomix S, Pennchlor-S)
> chlortetracycline/sulfamethazine/penicillin (Aureomix 500, Pennchlor SP)
> hygromycin B (Hygromix)
> lincomycin (Lincomix)
> OTC oxytetracycline (TM, OXTC, Oxytetracycline, Pennox, Terramycin)
> oxytetracycline-neomycin (Neo-Oxy, Neo-Terramycin)
> penicillin (Penicillin, Penicillin G Procaine)
> sulfadimethoxine-neomycin (RofenAid, Romet)
> tylosin (Tylan, Tylosin, Tylovet)
> tylosin-sulfamethazine (Tylan Sulfa G, Tylan Plus Sulfa G)
> virginiamycin (Stafac, Virginiamycin, V-Max)
* Additional drugs may be approved but aren't currently marketed for livestock. This is adapted from the FDA Center for Veterinary Medicine. The most current list of VFD drugs can be found at dvm360.com/vfddrugs.
> "Medically important" antibiotics in feed or water require a veterinarian. Any listed “medically important” antibiotics currently available in feed for animals will require a VFD (See "Drugs moving from OTC to VFD on Jan. 1”). In addition, medically important antimicrobials available to be used in water will require a veterinary prescription. Livestock producers will be required to obtain a VFD from their veterinarian for medicated feeds such as chlortetracycline (CTC) for anaplasmosis control and medicated milk replacers. However, ionophores, coccidiostats and anthelmintics as well as a few other antimicrobials will be exempt as they're considered “not medically important” in human medicine.
> VFDs must be filled through approved feed mills or feed distributors. As long as the feed distributor (co-op, feed mill, etc.) has a “letter of intent” on file with the FDA as well as an “acknowledgement letter” with the drug supplier or feed manufacturer, they'll be able to keep a stock of medicated feeds on hand to distribute to customers with a valid VFD. A veterinarian can write a VFD for multiple locations within a state owned by the same person as long as the feed is acquired from the same distributor.
> Veterinarians are responsible for the VFD. Veterinarians will be responsible for all information contained on the VFD. The veterinarian must be licensed in the state where the animals reside. A VFD will include both an expiration date and a specified duration of use. The expiration date refers to how long the VFD is valid for. This will be determined by either the product label or by the veterinarian's assessment of the animals' medical needs and cannot exceed six months from the time of issuance. The duration of use refers to the amount of time an animal or group of animals should be fed the medicated product. The duration of use will be specified by the labeled directions for that particular drug.
Other details on the VFD include number and type of animals being treated, condition being treated and level of antibiotic to be delivered. Telephone orders aren't allowed, although electronic means may be used to deliver the initial VFD request. The producer, veterinarian and feed distributor must keep records for two years. VFD manufacturers must keep product manufacturing records for one year.
> VFDs require a valid veterinarian-client-patient relationship (VCPR). Dispensing, prescribing or authorizing a prescription or VFD product requires a valid veterinarian-client-patient relationship (VCPR). It's illegal for a veterinarian to dispense or write a prescription or VFD for animals or herds they haven't seen or are unfamiliar with. Under the FDA Animal Medicinal Drug Use Clarification Act, this relationship exists only when all of the following conditions are met:
A valid veterinarian-client-patient relationship is one in which:
a. A veterinarian has assumed the responsibility for making medical judgments regarding the health of (an) animal(s) and the need for medical treatment, and the client (the owner of the animal or animals or other caretaker) has agreed to follow the instructions of the veterinarian;
b. There is sufficient knowledge of the animal(s) by the veterinarian to initiate at least a general or preliminary diagnosis of the medical condition of the animal(s); and
c. The practicing veterinarian is readily available for follow-up in case of adverse reactions or failure of the regimen of therapy. Such a relationship can exist only when the veterinarian has recently seen and is personally acquainted with the keeping and care of the animal(s) by virtue of examination of the animal(s), and/or by medically appropriate and timely visits to the premises where the animal(s) are kept.
Many states have their own definition of the VCPR, so veterinarians should review their state practice act and be familiar with the VCPR as it applies to them. But keep in mind that the FDA has determined that some states' definitions are not sufficient for VFD purposes-in these cases, the federal definition applies. (Check the FDA's current list at dvm360.com/vfdstates.)
In this new era, it's more important than ever that veterinarians stop and review the laws governing their livestock practice. Work with your clients to evaluate current and future medicated feed usage. Review the principles of judicious use of antimicrobials and herd health management practices. You may be able to reduce the need for antimicrobials with such disease prevention strategies as calving management, fly control and low-stress preconditioning programs for calves. Evaluate your and your clients' medical record-keeping practices, because new rules will require additional recordkeeping and documentation. The work you do today can help you better understand the VFD process and ensure that future implementation of any new drug laws in your practice will be even smoother and more painless.
Carla L. Huston, DVM, PhD, DACVPM, is associate professor in the Department of Pathobiology and Population Medicine at Mississippi State University's College of Veterinary medicine.