Detection of BRD pathogens in relation to clinical signs of case and case-control veal calves

Abstract

This paper describes a study aimed at quantification of the prevalence of several known bacterial and viral pathogens, clinical signs and additional conditions leading to Bovine Respiratory Disease (BRD) in veal calves in the Netherlands. For this purpose 168 veal calves with a respiratory rate (RR) higher than 50 rates per minute (cases) and 573 calves with a RR lower than 50 rates per minute (case-controls) were subjected to bronchoalveolair lavages (BAL’s) and clinical evaluations, on conventional Dutch veal farms. The most prevalent pathogen was Pasteurella multocida, detected in 29% of cases and in 33% of case-controls. Statistically, Arcanobacterium pyogenes, Bovine Parainfluenza and Bovine Viral Diarrhea Virus had higher a prevalence in cases than in case-controls. Clinical signs were significantly more often detected in cases, in both viral and bacterial pathogens. Of the cases 45% had an elevated rectal temperature, 24% was in respiratory distress, but just 6% showed coughing. Analysis showed there was no significance between severity of clinical signs and a specific pathogen related to BRD in cases and case-controls.