Treatment of Calves with Bovine Respiratory Disease: Duration of Therapy and Posttreatment Intervals.

When treating bovine respiratory disease, it is important to consider the decision to initiate treatment, the treatment regimen used, and whether to continue treatment. It is necessary to define the duration of drug exposure and when a success/failure decision will be made. No data are available to define the optimal duration of antimicrobial exposure. A pattern seen in human pneumonia studies is that shorter durations of therapy were equivalent with longer durations. Some studies suggest defining success or failure based on pharmacokinetics and pharmacodynamics may lead to earlier than optimal intervention. Optimal intervals are best defined by randomized clinical trials.