Aureomix S finding its niche, and then some, in VFD era
An interview with
Thomas Painter, DVM
US Pork Technical Services
Q: Aureomix S is a feed medication for swine that contains chlortetracycline and sulfamethazine. Both antibiotics are considered medically important by FDA. What’s the future in the US pork industry for a two-in-one antibiotic?
TP: I think the future for this product is bright. Obviously, under the new rules, veterinarians need to issue a veterinary feed directive (VFD) to the feed mill and producer before they can use it. But other than the extra paper work, I don’t see the VFD changing the way Aureomix S is used. Veterinarians regard sulfamethazine and chlortetracycline as a dependable combination, but they also recognize it needs to be used responsibly — at the right time, for the right reason. That’s always been the case. The VFD just makes everyone more accountable.
Q: Chlortetracycline and sulfamethazine are often described as broad-spectrum antibiotics. But under current rules, veterinarians need to check off a specific indication for use on the product’s VFD form. Does this requirement sometimes present a challenge for veterinarians?
TP: Yes, it does. Over the past few decades, the regulatory climate has made it difficult and costly for animal-health companies to add new indications to established products, especially antibiotics. As a result, the product labels of some feed medications have not kept pace with today’s disease pressures or management practices.
Q: So, does that make these products obsolete?
TP: Not at all, but it does underscore the importance of the VFD and the need for a veterinarian-client-patient relationship (VCPR). As we all know, it’s rare to find one specific pathogen causing enteric or respiratory disease in a swine herd. It’s usually a combination of bugs — a syndrome or a complex — working together, with one pathogen opening the door for another.
If a veterinarian makes a clinical diagnosis and believes that several pathogens have infected the herd, he or she can draw on his or her scientific knowledge and experience and recommend a medication he or she believes will be effective against at least one of those organisms. Likewise, if a lab test shows a certain pathogen is present, a skilled veterinarian will know that bug’s relationship to others. That, in turn, provides some flexibility in matching the product indications to the health problem at hand. But again, this underscores the importance of the VCPR. The veterinarian knows the producer, herd and farm’s history.
Q: Can you give an example?
TP: Take Aureomix S, for instance. The label says it can be used “in the presence of atrophic rhinitis (AR).” Well, we don’t see many acute cases of AR anymore, and extra-label usage is not permitted. However, it’s widely accepted that two pathogens we do often see today — Pasteurella multocida and Bordetella — cause AR. That said, if there’s a respiratory outbreak on a farm I know, and if performance is down and I suspect or know that either of those pathogens is in the mix, I’d feel comfortable issuing a VFD for a medication with an AR claim — in this case, Aureomix S. When I was a swine-production veterinarian, we frequently used Aureomix S in the nursery because we knew these pathogens were related to AR.
Q: So, while veterinarians must read and follow the product label, it seems that issuing a VFD involves a lot more than connecting the dots between a product’s label and a specific pathogen.
TP: Exactly. Look, when pigs are sick or on the verge of getting sick, veterinarians need to respond quickly. As I said earlier, it’s unusual in swine production to find any one pathogen working on its own. There’s usually a connection to at least one other pathogen. My point is that anyone can read a product label. It takes a veterinarian and a VCPR to practice good medicine — and that’s what we’ve taken an oath to do. Before we can check off a box on the VFD form, we need to step out of the box and look at the big picture. What’s going to solve the problem quickly, effectively and responsibly? What clinical experience can we draw on to justify a particular product’s use? The key is to document these evaluations in a site report. Write it down, date it, sign it.
Q: Getting back to the Aureomix S label, there’s a claim for “reduction of the incidence of cervical abscesses.” Where does that come into play?
TP: Cervical abscesses begin when bacteria enter the body — usually through a wound, a puncture in the skin or even external orifices — and then settle in the lymph nodes in the jowl or neck. Cervical abscesses generally don’t become a health issue on the farm. However, they can be a major economic problem at the processing plant, where they can lead to some parts being rejected and reductions in carcass yield. Unfortunately, what happens to the head at the packing plant isn’t always well documented. As a result, this is a problem that’s often poorly communicated by the packer. If carcasses are losing yield from cervical abscesses — and you may not know they are until you look into it — Aureomix S is one possible solution. Changing needles while administering vaccines or injectable antibiotics is another way to help prevent these abscesses.
Q: Aureomix S is also indicated for the prevention of certain diseases — bacterial enteritis, for example —“during times of stress.” From a medical standpoint, what constitutes stress?
TP: Weaning, the onset of disease, major changes in weather, mixing pigs, new caregivers — all of these situations can stress pigs. Stress and disease go hand in hand. As long as there’s a VCPR and stress is documented in a site report, that claim gives veterinarians a lot of flexibility when recommending this medication.
Q: What’s the treatment window for Aureomix S?
TP: It’s flexible but needs to be specified by the veterinarian. With a veterinarian’s approval, a producer could keep feeding Aureomix S until pigs are done with that batch of feed. Their only concern is the withdrawal time, which is 15 days.
Q: What if the producer’s feed mill has a policy prohibiting the use of sulfamethazine?
TP: Fortunately, that’s a small percentage of the feed industry, but it’s an area where we need more education. If the mill’s concerns are perception-based, we need to respect that and realize it’s difficult to change their position. If the mill’s concern is science-based, that can be overcome. The all-granular formulation of Aureomix S has pretty much eliminated the risk of sulfa spikes in flush feeds that used to be common with non-granular products. On the farm, most pigs are on slatted floors, not concrete or dirt, so that’s greatly reduced the risk of fecal contamination. Aureomix S is an easy product to manage and, more importantly, extremely valuable for maintaining the health and welfare of today’s swine herds.
Posted on February 1, 2020