Efficacy of Tulathromycin and Oxytetracycline on Reducing the Incidence of Otitis Media Caused by Mycoplasma bovis in Preweaned Holstein Dairy Calves

Abstract

The Land O'Lakes Research facility in Webster City, IA conducts trials on three- to five-day-old Holstein bull calves purchased from sales barns located in Wisconsin. Calves are sold to producers after completion of the research trials. During the past seven years, Mycoplasma bovis has reduced the value and number of saleable calves primarily due to otitis media and subclinical pneumonia. To better understand the transmission dynamics of M. bovis and the potential therapeutic benefit of prophylactic antimicrobial drugs, a study was initiated to evaluate calf growth, health, treatment costs and isolation rate of M. bovis from the pharynx of calves housed at the facility.