Pathogenic assessment of chicken embryo fibroblast cell culture adapted infectious bronchitis virus vaccine.

摘要

Adaptation of prevailing embryonated chicken egg (ECE) adapted infectious bronchitis mass serotype vaccine viruses in chick embryo fibroblast cell culture (CEFCC) was attempted. Presence of the virus was assessed qualitatively (observation of specific lesions in ECEs and specific cytopathic effect in active passage levels) and effect on pathogenicity was assessed quantitatively (titration in ECE and microtitration in CEFCC system). In addition, the presence of virus was confirmed by micro haemagglutination (HA) and rapid plate HA tests. However, the high protective titres of the corresponding "startup" viruses could not be achieved. Hence, a few more passages in TC system may be advocated, thus enabling to achieve an effective pentavalent vaccine against IB.