Characterization of a highly virulent Avibacterium paragallinarum isolate.

Vaccination with inactivated multivalent vaccines is a primary strategy to control Infectious coryza. Avibacterium paragallinarum serotyping is important for effective protection as inactivated whole-cell vaccines provide protection against only the serogroup or serovar from which the vaccine was derived. In this study, a novel serovar within the serogroup C Avibacterium paragallinarum isolate ZJ-C has been characterized first time in China. It was highly virulent and induced 100% cross-protection to Modesto bacterin vaccinated chickens, but not the other way around.