Abstract: The characteristic of IBV-M41 and IBV-Ma5 strains cultured in tracheal organ was assessed by the ciliary activity of chicken embryo tracheal organ. After the virus (containing 100TOCID50) was inoculated into trachealring organ cultures, the survival rates of cilia were assessed . The results showed that the survival rates of epithelial cells inoculated with IBV-Ma5 was high than with IBV-M41, which means their culture characteristics accord with their toxicity.

Key words: tracheal organ cultures(TOC); infectious bronchitis; characteristic of cultrues