Nasopharyngeal swabs, 1-2 mL transtracheal wash, 1-2 mL bronchoalveolar lavage, and respiratory tissues such as 1.0 g of fresh or frozen lung or trachea.
Detection of antibodies to bovine herpesvirus type 1 (VN), the causative agent of infectious bovine rhinotracheitis (IBR) virus, by virus neutralization.