Comparison of hemagglutination-inhibition, agar gel precipitin, and enzyme-linked immunosorbent assay for measuring antibodies against influenza viruses in chickens.

Individual variations in serological response to avian influenza virus infection were demonstrated after experimental infection of specific-pathogen-free chickens with H6N2 influenza virus. Homologous antibodies were detected from the 6th to the 157th day after infection using hemagglutination-inhibition or enzyme-linked immunosorbent assay and from the 11th to the 157th day by agar gel precipitation test.