Abstract
Bovine respiratory disease (BRD) impacts beef cattle health and farming systems. To better understand the BRD predisposing factors, a study was conducted in northwest Italy on a population of 26 batches (760 animals) of beef cattle imported from France. Of these, 173 underwent physical examination for clinical signs of BRD (rectal temperature > 39.5 °C, respiratory rate > 36 bpm, cough, nasal or ocular discharge) and blood sampling to detect antibodies against bovine viral respiratory infectious agents (e.g., parainfluenza 3, bovine herpesvirus type 1), haptoglobin and reactive oxygen metabolites concentrations, on arrival. Data on BRD treatments performed within 60 days of arrival were extracted from farm registers. The two most frequent cattle breeds were Blonde d'Aquitaine (80/173, 46.2%) and Limousine (61/173, 35.3%); the median batch weight was 332 kg (range, 195-470). At least one clinical sign of BRD was noted in 57.2% (99/173) of the animals. Most animals tested positive for BPIV3 (131/173, 75.7%) and BRSV (112/172, 64.7%). Bovine respiratory disease treatment was associated with transport time and average weight on arrival. Moreover, reactive oxygen metabolites levels differed between treated and untreated animals; this difference could help predict the onset of BRD, though further studies are needed to draw conclusions.