Comparative efficacy of tilmicosin, florfenicol, and fiorfenicol-flunixin meglumine for treatment of undifferentiated fever in backgrounded winter-placed feedlot calves given tilmicosin metaphylactically on arrival

Abstract

A study was conducted in 3 feedlots to compare the clinical efficacy of tilmicosin to florfenicol and florfenicol-nunixin meglumine for the initial treatment of undifferentiated fever (UF) in backgrounded winter-placed feedlot calves treated metaphylactically with tilmicosin at arrival processing. No significant differences (P>0.05) were found in UF relapse rates, crude case fatality rates, bovine respiratory disease and histophilus fatality rates, or average daily gain between the 3 groups. The cost benefit of tilmicosin versus florfenicol and florfenicol-flunixin meglumine was based on the difference in treatment cost between the 3 drugs. Using current market prices and a treatment weight of 828 lb (376 kg), the cost of treatment with tilmicosin was $15.85 CAN less per head compared to treatment with florfenicol, and $15.90 CAN per head less than florfenicol-flunixin meglumine.