PSXIII-B-17 Risk of Bovine Respiratory Disease by Pathogen Incidence

Abstract Bovine respiratory disease (BRD) affects millions of cattle in the US annually. This study sought to identify commensal pathogens animals without clinical signs that were predictive BRD using Wisconsin Health Scoring (WHS) system. Cases healthy later diagnosed with (WHS ≥ 5.0), positive controls (PC) at time initial sampling and negative (NC) those remained throughout ≤ 4.0). Beef feedlot sampled Colorado (CO; cases = 13, NC 500, PC 488) Washington (WA; 5, 499, 506). Preweaned Holstein dairy calves from California (CA; 73, 1017, 1003) New Mexico (NM; 25, 381, 376). For each animal, mid-nasal deep pharyngeal swabs used test for nine pathogens. ANOVA testing (P< 0.05) odds ratios (OR) calculated population. In CO, bovine viral diarrhea virus (P 0.0001, OR 13.1) Histophilus somni 0.008, 4.2) would be while syncytial (BRSV; P 1.1 × 10-6, 40.8) was most WA. NM, BRSV 0.005, 5.8) also BRD. No pathogen risk CA. Prevalence higher < than suggesting incidence taken diagnosis may not reflect initiating disease. These results highlight geographical differences which should considered when managing reduce