Using thoracic ultrasonography to investigate the impact of antibiotic therapy on the health and performance of preweaned dairy calves

摘要

Bovine respiratory disease (BRD) continues to be a major cause of morbidity and mortality of preweaned dairy calves. Costs associated with this condition include drug and labor costs as well as loss of animal productivity. Recent use of clinical scoring systems and thoracic ultrasonography allows for the diagnosis of different BRD subtypes including upper respiratory tract infection, clinical pneumonia, and subclinical pneumonia (Ollivett and Buczinski, 2016). Previously, the impact of antibiotic therapy has not been evaluated on these different BRD subtypes. Therefore, the objective of this study was to determine the impact of antibiotic therapy on the health and performance of preweaned dairy calves affected by different BRD subtypes.