Field Trial Comparisons of Nuflor® (florfenicol) to (1) Naxcel® + Penicillin G, and (2) Nuflor to Naxcel.

Bovine respiratory disease (BRD) is unequivocally the most economically important disease of cattle in feedyards. Each year hundreds of millions of dollars are lost through death, reduced performance, and costs of medicine and labor. Cost-effective therapy for BRD, therefore, is a primary consideration for cattle feeders. However, decisions regarding health management, including respiratory disease therapy, are often based on perception or hearsay rather than data or records which reflect the actual situation.

Since the introduction of Nuflor in 1996, Merck Animal Health has implemented an active program to support customers with "real-world" studies conducted on their operations to prove the cost-effectiveness of Nuflor versus current feedyard therapies.


A 30,000-head feedyard in the Oklahoma panhandle had removed NUFLOR from its first-line treatment program in the fall of 1996. Management stated that repull proportions with NUFLOR were "too high" as compared to the standard treatment (Naxcel + Penicillin G) in that feedyard, although a specific definition of "too high" was not offered.

To more specifically define the yard’s treatment response rate and to attempt to demonstrate clinical efficacy and cost-effectiveness of NUFLOR as compared to the standard treatment program, management agreed to SPAH’s offer to conduct a field trial at the feedyard. SPAH provided the trial protocol, randomization schedule, necessary training, and data collection and analysis in cooperation with the consulting veterinarian.


Animals pulled for respiratory disease treatment were randomly assigned to treatment groups, NUFLOR or Naxcel + Penicillin