Protection conferred by live infectious bronchitis vaccine viruses against variant Middle East IS/885/00‐like and IS/1494/06‐like isolates in commercial broiler chicks

The ability of the infectious bronchitis H120 (a Massachusetts strain) and CR88 (a 793B strain) live attenuated vaccine viruses to protect from two Middle East infectious bronchitis virus isolates, IS/885/00‐like (IS/885) and IS/1494/06‐like (IS/1494) in broiler chicks was investigated. Day‐old chicks were separated into three groups, (I) vaccinated with H120 at day‐old followed by CR88 at 14 days‐old, (II) vaccinated with H120 and CR88...