This article provides some clarity for when new products or combinations of products come onto the market.
These days all antimicrobials, NSAIDs and a few other products are prescription products and most come under the VCPR (veterinary-client-patient relationship). The two products in this case have already been on the market for years, but now, with no advertising on these prescription drugs, the huge teaching burden falls on the veterinary profession.
Sometimes your veterinarian is too busy or not familiar enough with the products or may not deal that much with the actual pharmaceutical company that manufactures them.
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Producers can educate themselves on new emerging products that enter the marketplace, as they may benefit your operation or management style. You all need to realize any new and old products before them have passed rigorous testing and even though they may be generics (lookalikes), they have passed the same testing as the original product.
If you find the name of a product, veterinarians can find it on the Veterinary Compendium, where it will have the label described. Understanding how other producers use and their veterinarians prescribe a medication is great information, but make sure to get accurate information and not just hearsay.
Two similar products are Resflor and Zeleris. Both these products contain florphenicol, which has a good effect on respiratory pathogens. The products also contain an NSAID, giving anti-inflammatory or pain control as well. The antibiotic is the same and both trade names are used for pneumonia as prescribed by veterinarians.
There are other conditions where they are the top choice, but your veterinarian can advise you as to what product for what condition. Florphenicol is a Category 3 antibiotic, so we want to use it on cattle as a first choice, as there is little crossover in human medicine.
These two products have slight differences. When similar products are launched, the new soft, subtle, potentially convenient things are what may excite the vet and/or producer.
Zeleris has three features worth considering. It comes in a plastic bottle, it has a lower dose than Resflor and it is more syringeable.
There are great plastics out there these days and I hope the regulatory people will approve more and more antimicrobials in plastic bottles. This makes sense from a wastage, breakage and recycling perspective. From breakage during shipping to needing protective plastic shrouds around them, there is much more cost and wastage with glass. Plastic is the best new way to go as it is user-friendly. I know of several antimicrobials in plastic bottles, so I see no reason why all can’t be.
A lower dose adds convenience but the product Resflor, despite being six c.c. per 100 pounds, was used extensively because the efficacy was so darn good. If efficacy is excellent, a lot of inconvenience can be tolerated. Zeleris is a bit lower at 4.5 c.c. per 100 lbs., for a slight convenience on administration.
Syringeability only really comes up in colder weather, and I know the company that makes Resflor provides bottle warmers to try and keep the product as syringeable as possible.
Despite the high dosage of either product, there’s rarely an event with swelling. That’s why one needs to try these products to see the degree of swelling and make your judgment. I found it interesting that on the label of Zeleris, the amount in one site is 15 c.c. and virtually everything else is at 10 c.c. I believe this company went ahead and did the testing to get the 15 c.c. on the label. That is admirable.
For another advantage, the florphenicol molecule shows very little resistance and it is a safe Category 3 antimicrobial. That’s very good news for cattlemen — not to mention that two separate companies make these very similar products. Two similar products will tend to erode the price, and, in many ways, they can be used interchangeably — but check with your veterinarian first, and remember the dosage difference.
I have experience using both products and you will appear to get a quicker response with the Resflor because the banamine lowers temperature quickly. I see no difference in the recovery of sick calves and getting them back onto feed.
All florphenicol products have longer withdrawals and Zeleris is no different, with a 56-day withdrawal; Resflor has a 60-day withdrawal.
The good news is these drugs are used in calves on cow-calf enterprises and feedlot cattle shortly after entry. With the long withdrawal, it’s best to keep away from use on heavy feedlot cattle.
We need multiple pharma companies to keep markets competitive and innovative. Amazingly, features like a plastic bottle or ease of administration can be important decisions in which product we choose, both as veterinarians and producers.
Always remember, availability may have you moving between products — but practice prudent use with your veterinarian. The first decision is whether antibiotics are needed or not.
