Livestock producers and veterinarians recently gained a bit more insight into the changes they’ll be facing in the way antibiotics are used in food animals. Back in December 2013, the Food and Drug Administration (FDA) published “guidance for industry” documents that outlined, among other changes, how the Veterinary Feed Directive (VFD) will become a critical component of food animal feed-grade antibiotic use. This June, the FDA came out with their “final rule” regarding how the VFD will be used – providing more detail about this classification of feed-grade antibiotics.

Label changes coming

The changes outlined in 2013 will remove the labeled indications for the use of feed-grade antibiotics for growth promotion and feed efficiency. Each manufacturer of these products has agreed to make these label changes before the full implementation date of December 2016. Since extra-label use of feed-grade antibiotics in food animals is illegal, these uses will no longer be allowed.

Medically-Important classification set to change

Another huge change outlined earlier will change the classification of “medically important” feed-grade antibiotics from their current over-the-counter status to the VFD designation. The list of what FDA considers “medically important” antibiotics is pretty long. It contains common drugs like tetracyclines and penicillin along with classes of drugs more critical to human medicine, such as cephalosporins and fluoroquinolones. Producers and veterinarians can still use these medications, but they will be limited to uses for prevention, control, and treatment of illnesses in food animals – and they will require a VFD form prior to their use.

Having been around since the late 1990’s, the VFD is not a new concept. Any new feed-grade antibiotic preparation approved for use since then has carried this designation. In order to use these products, such as Pulmotil® for pigs and cattle and Nuflor® for pigs and fish, producers have needed to get a VFD form (similar to a prescription) from a veterinarian prior to use of the drugs. The changes proposed by the FDA will expand the use of the VFD to many common feed-grade antibiotics currently used by food animal producers.

The VFD final rule recently released spells out the VFD in more detail. The veterinarian will fill out the form, specifying the farm and animals to be treated, the drug to be used, its feeding rate, and the duration of treatment.

The FDA has made allowances for a VFD to apply to groups of animals that may be moved to different locations, such as weaned pigs moved from a nursery to a grower, as long as the different locations are listed by the veterinarian on the VFD.

The veterinarian will consult the antibiotic label to list feeding instructions on the VFD in terms of the inclusion rate and duration of feeding – for example, “feed at a rate of 500 mg [of drug] per head daily for 14 days.” The veterinarian will also indicate an expiration date on the VFD. This is will typically be spelled out on the product label, but can’t exceed 6 months. The expiration date can be thought of as an “authorization” to feed the drug. For the example given above, once a producer procures the VFD, he would have 6 months to complete the 14 day course of treatment. Some drug labels may allow for a number of “refills,” which (in this example) means the producer might be able to obtain feed for more 14-day course(s) of treatment if the VFD hasn’t expired. Once a VFD expires, that authorization is gone, and a new VFD must be procured.

The feed mill or distributor is required to have a properly completed VFD form on hand before they can supply the feed. The final rule indicates that the VFD form could be sent electronically from the veterinarian to the feed mill via e-mail or an internet service, but it can’t be simply “phoned in” by the veterinarian. The feed mill, veterinarian, and producer will all need to keep a copy of the VFD on file for two years.

In the case of drugs fed in approved combinations, if any of the drugs in that combination are VFD drugs, a VFD will be required for that feed.

The VFD won’t be able to be written by just any veterinarian. Only a veterinarian – licensed in the state where the animals are present - with a valid veterinary-client-patient relationship (VCPR) with the operation and animals is allowed to write a VFD. The FDA will defer to each individual state’s definition of the VCPR, as long as it meets some basic criteria. In cases where states do not have their own definition (South Dakota is one of those states), the federal VCPR definition will come into play. The fact that the FDA does not define the VCPR in terms of specific number of farm visits or patient examinations may frustrate some, but allows for the flexibility necessary to serve the wide variety of today’s food animal operations.

The VFD final rule will be implemented on October 1, 2015, but some feed grade medications might not have changed their labeling before that time. Once the antibiotic manufacturer applies those updated VFD labels to their products, VFD’s will need to be written before they can be used. All manufacturers will need to have those changes made by the full implementation date of December 31, 2016.

As a reminder, some livestock medication practices won’t change at all in light of these regulations. The use of non-“medically important” feed-grade products are an example. Obtaining and using ionophores like Rumensin®, Bovatec®, most coccidiosis medications, and certain growth-promoting medications such as bacitracin (BMD®) will not change, since they’re not used very often if at all in human medicine. As has always been the case, extra label uses of feed-grade medications are illegal, and they will remain so.

Uses of injectable antibiotics are not slated for change. However, the changes outlined in 2013 will also move over-the-counter medically-important water medications to “prescription” status like many injectable antibiotics.

Current distributors and feed mills will retain the ability to supply these products to producers. Of course there will be more paperwork because there will be more VFD forms to keep track of, but these changes do not limit these businesses in what they can carry or manufacture.

One aspect of food animal production was important prior to these changes and will remain important afterwards—the need for veterinarians to be involved in decisions about feed-grade antibiotics. There is no better source of information about the proper uses of these products in livestock populations than the herd veterinarian. A close relationship with a veterinarian means less time and money wasted on ineffective uses of these products, and more practical advice to help prevent the illnesses that require antibiotic use in the first place.

Antibiotic resistance is a complex and sometimes contentious topic among animal and human health professionals. The complexity of the issue means that a “silver bullet” solution is not going to present itself any time soon. All of us involved in using these products—in animals and people alike—play a role in ensuring that they continue to work for the sake of our animals and our family members. Understanding these proposed changes and proactively deciding how they will work into your operation is a great first step that we can all take.

Disclaimer: Product trade names are used for purposes of illustration only and do not constitute an endorsement of those products.