The nasopharyngeal microbiota of pre-weaned dairy calves with and without ultrasonographic lung lesions

The primary objective was to compare diversity and taxa characteristics of the nasopharyngeal microbiota between pre-weaned dairy calves with and without ultrasonographic evidence of Bovine Respiratory Disease (BRD) and among categories of BRD severity based on ultrasound. BRD is a prevalent and complex cause of morbidity and mortality in dairy calves. The upper respiratory tract microbiota includes commensal bacteria that play a central role in the development of BRD in calves. Characterizing the nasopharyngeal respiratory microbiota of dairy calves will improve the understanding of BRD pathogenesis and contribute to further development of potential prevention strategies.