COMPARISON OF ETIOLOGIC AND IMMUNOLOGICAL CHARACTERISTICS OF 2 ATTENUATED ERYSIPELOTHRIX-RHUSIOPATHIAE STRAINS OF SEROTYPE-1A AND SEROTYPE-2

Two acriflavine-fast attenuated Erysipelothrix rhusiopathiae strains K oganei 65-0.15 of serotype 1a (strain Kg-1a) and 2 (strain Kg-2) were comparatively characterized, Biochemical characterization showed the s imilar reactions with slight variation between the strains. Strain Kg- 2 was more resistant to acriflavine dye than strain Kg-1a. Pathogenici ty of strain Kg-2 was higher than strain Kg-1a in mice of strains ddY, C3H/He and A/J. Significant differences of clinical signs between str ains Kg-1a and Kg-2 were observed in occurrence of arthritis (P<0.05) and systemic signs (P<0.01) of only ddY mice. C3H/He mice was more res istant than ddY and A/J mice to the infection of strains Kg-1a and Kg- 2. Three culture fractions, whole culture: WC, culture filtrate: CF an d killed cells: KC, of strain Kg-2 were more protective than those of strain Kg-1a in ddY mice. CF of strain Kg-2 was most protective in all fractions. Heating at 56-degrees-C and 100-degrees-C or treatment wit h trypsin completely reduced the protective activity of WC of the two strains, indicating that major protective antigens of WC were protein. The present results demonstrated that immunogenicity and pathogenicit y for mice were different between the two attenuated strains.