Clinical Efficacy of Danofloxacin in Pneumonic Feedlot Cattle

Abstract

Bovine respiratory disease is the most common disease associated with recently transported cattle in North American feedlots. Retrospective data collected in 1984 from commercial feedlots in Texas indicate that 83% of total morbidity and 66% of total mortality was attributable to respiratory disease¹. A review of feedlot data from Kansas and Nebraska in 1987 reported similar results with 79% of total morbidity and 67% of total mortality attributed to respiratory disease².

Danofloxacin* is a novel, potent third generation fluoroquinolone which has bactericidal activity against a broad spectrum of bacteria and mycoplasmas of veterinary importance. Minimum inhibitory concentrations expressed as MIC 90' s of danofloxacin to a large sampling of common bovine respiratory pathogens Pasteurella haemolytica, P. multocida and Haemophilus sommus have been reported at 0.25, 0.125 and 0.25 μg/ml, respectively3.

This trial was conducted to confirm the therapeutic efficacy of danofloxacin in the treatment of naturally occurring bovine respiratory disease in a research feedlot facility in Texas which maintains management practices typical for the commercial feedlots in the area. Efficacy was assessed based on the reduction in pyrexia, improvement in clinical condition, reduction in number of response failures, prevention of mortality, and the maintenance of normal weight gain.