Experimental infectious bovine rhinotracheitis: comparison of four antigen detection methods.

The duration of detectable viral antigen in nasal secretions was studied by four methods in calves experimentally infected with infectious bovine rhinotracheitis. Virus isolation in cell culture was the most sensitive and was successful for up to 11 days after inoculation. Three direct rapid antigen detection systems (immunofluorescence, immunoperoxidase and enzyme-linked immunosorbent assay [ELISA]) were all successful during the pyrexic phase, but less useful in the later stages of the disease. Virus isolation and ELISA remained positive in strongly positive samples stored for a week at room temperature.