5) Infiltration of neutopphils in bronchiolar lumen, and infiltration of neutrophils and macrophages in surrounding alveoli.

6) Hyperplasia of lymphatic follicles at the surrounding area of the bronchus.

7) U.diversum isolated from mucous membrane of the bronchus(deep dark small colonies) and Mycoplasma bovirhinis (eye-ball shaped colonies).

8) Identification of Mycoplasma using growth inhibition test.