Evaluation of 3-, 6- and 9-day post-treatment intervals following pradofloxacin for treatment of bovine respiratory disease in stocker cattle

Pradofloxacin is a fluroquinolone antimicrobial approved for treatment of bovine respiratory disease (BRD) in cattle in the United States. The primary objective of this study was to compare different post-treatment intervals (PTI) follow­ing therapy with pradofloxacin on first treatment success and case fatality in stocker cattle naturally affected with BRD. The days-to-death (DTD) following enrollment was evaluated as a secondary outcome. Cattle at 5 commercial stocker operations were identified with BRD by site personnel and were random­ized in a 1:1:1 ratio to 3-, 6- or 9-day PTI within each cohort. Following treatment with pradofloxacin, cattle were followed for 45 days to monitor health outcomes. First treatment suc­cess was defined as no additional treatment for BRD and no mortality. Case fatality was defined as death due to any cause. Generalized linear mixed models were used for statistical analysis. Weight at treatment and rectal temperature were not different between PTI groups. First treatment success (P = 0.51) and case fatality (P = 0.52) were not different among PTI treatment groups. DTD was not different between PTI treatment groups (P = 0.20). These results will assist with de­termining optimal use of pradofloxacin in stocker cattle.