The mainstays of treating respiratory disease in cattle include two things:
a targeted, effective respiratory antibiotic, and
an anti-inflammatory.
Both of these are important for timely treatment of pneumonia. Most acute respiratory cases start from infection with a virus (often presenting as a high fever and puffing), which then weakens the animal’s immune defenses and allows for secondary infection with bacteria (which often presents as cloudy nasal discharge, coughing, lower grade fever and respiratory effort). Prompt treatment then requires both an anti-inflammatory to bring down fever and manage the inflammatory response, and antibiotics to reduce the secondary bacterial infection.
For many years, Resflor has been a staple in treating pneumonia in non-lactating cattle. It was the first combination product that included both an effective antibiotic and an anti-inflammatory in a single injection. However, just this December, Ceva Animal Health released its competitor product called Zeleris. There are a few differences between Resflor and Zeleris that makes Zeleris a better product.
Resflor is a combination of Florfenicol (a broad spectrum respiratory antibiotic - trade name Nuflor) and the non-steroidal anti-inflammatory drug Flunixin (trade name Banamine or Flunazine). The antibiotic portion of Resflor maintains high levels of activity in the lungs for 4 days after one dose, so it is not recommended to repeat Resflor sooner than 4 days after the first dose. The problem with this is, the Flunixin anti-inflammatory portion really only lasts about 12-24 hours. For this reason, if it seems that Resflor isn’t working on the second or third day after treatment, it’s likely that the anti-inflammatory has worn off and the animal’s fever has returned. For this reason, it is common for us to recommend repeating the anti-inflammatory on day 2 or 3 of treatment, so a shot of metacam or 2 days of Banamine/Flunazine to help reduce fever and help with the pain associated with pneumonia. Resflor can then be repeated on day 4 after the first dose. This is usually effective, since for acute viral pneumonia the anti-inflammatory portion is most important, rather than changing antibiotics. However, it involves using more than just one drug, which kind of defeats the purpose of using a combination product.
The new product, Zeleris, is a combination of Florfenicol and Meloxicam (Metacam). Meloxicam’s duration of activity is 2-3 days, which makes it a more ideal match in a combination product where the anti-inflammatory effect matches more closely in duration with the antibiotic. This means there is no need to add in extra anti-inflammatory therapy in between days - it can truly be a one-shot treatment. Other attractive qualities of Zeleris include: a slightly shorter meat withdrawal (56 days), a plastic bottle, better syringe-ability, a smaller dose (4.5 mL per 100 lb), and it is comparative pricewise per mL with Resflor.
Studies by the manufacturer have demonstrated efficacy of Zeleris, and also showed good results comparing it to Resflor in the field, including better cure rates and reduction in relapses (return of fever). If you are interested in trying Zeleris for treating respiratory disease, please call the clinic or ask one of our vets.