ISOLATION AND IDENTIFICATION OF INFECTIOUS-BRONCHITIS VIRUS FROM CHICKENS IN SICHUAN, CHINA

A nonhemagglutinating virus was isolated from kidneys and lungs of chi ckens suspected of having infectious bronchitis infection. Specific-pa thogen-free embryonated chicken eggs were used as the cultural system. With the use of the ciliary activity of chicken embryo tracheal organ cultures as indicator system, the physicochemical properties of one o f the isolated strains (SAIB(3)) were shown to be similar to infectiou s bronchitis virus (IBV) strain M-41 (standard strain); whereas electr on microscopy of the isolate showed coronavirus particles. Virus-neutr alization tests were performed in trachea organ cultures to compare th e serotypes of five IBV isolates and six known IBV strains on the basi s of reciprocal neutralization titers and euclidean distance. The cros s-neutralization pattern indicated that one isolate was of the T-strai n IBV serotype, another of the M-41 IBV serotype, while others had par tial serotype relationship to M-41 and T-strains of IBV.