Abstract: Mycoplasma ovipneumoniae, the cause of a typical pneumonia of sheep and goats, is responsible for important economic losses in ovine industry worldwide. The aim of this study was to develop an inactivated Mycoplasma ovipneumoniae vaccine. Mycoplasma ovipneumoniae isolate SC02 was screened and cultured in modified Thiaucourt's broth media and harvested when the titers reached 10⁹ CCU/mL. The cultures were concentrated 20 folds as antigens for oil adjuvant vaccine preparation. Six-month-old goats which without Mycoplasma ovipneumoniae antibody were injected subcutaneously with 5.0ml(2×10¹⁰ CCU/mL) the vaccine. 21 days after immunity, the goats, including tested and controlled goats, were tracheally inoculated with 5.0 mL(≥2×10¹⁰ CCU/mL) highly virulent Mycoplasma ovipneumoniae strain Y98,and the temperature and clinical symptoms were observed daily.All goats were dissected to observe pathological changes post 30 days of injection of Y98 strain. The results showed that all five goats inoculated vaccine did not appear clinical symptoms and pathological changes; conversely, the control goats had developed clinical symptoms with cough, fever, runny nose. Moreover, typically lung pathological changes of Mycoplasma ovipneumoniae were observed in controll ainmals in anatomical examinations. The results showed that the vaccine developed in this study can protect goats effectively against Mycoplasma ovipneumoniae.

Key words: Mycoplasma ovipneumoniae; clinical isolates; inactivated vaccine