Examination of the pharyngeal tonsil transcriptome response to Bovine herpesvirus 1 (BoHV-1) infection in dairy calves

Bovine Herpesvirus 1 (BoHV1) is a leading cause of Bovine Respiratory Disease (BRD) in young calves, which is responsible for substantial morbidity and mortality. Therefore, the objective of the current study was to elucidate the mRNA transcriptomic response in pharyngeal tonsil tissue to an experimental challenge with BoHV1, in dairy calves. Holstein-Friesian calves were either challenged by intranasal atomisation with BoHV1 virus (6.3 x 10^7/mL x 1.35mL) (n=12) or mock challenged with sterile phosphate buffered saline (n=6). Clinical signs were scored daily until euthanasia at day 6 post-challenge. Total RNA was extracted and sequenced from pharyngeal tonsil (100 bp paired-end). Sequence reads were aligned to the ARS-UCD1.2 bovine reference genome and differential gene expression analysis was performed using EdgeR. Anlysis uncovered a total of 1833 differentially expressed genes (p < 0.05, FDR < 0.1, fold change > 2) between the BoHV-1 challenged and control calves. Examination of a single tissue type (pharyngeal tonsil) in two different treatment groups, BoHV-1 challenged calves (n=12) and control calves (n=6)