| Popis: |
In the present work, we attempted to characterize 4 field strains of Salmonella cholerae-suis var kunzendorf susceptible to antibody and complement (Ab-C), and 4 strains not susceptible to Ab-C, with respect to their virulence for mice and pigs. In vivo growth of an Ab-C-susceptible, mouse-virulent strain in the spleens of mice exceeded that of 2 Ab-C-susceptible, but mouse-avirulent strains by at least 10(4) organisms. Comparison of Ab-C susceptibility with virulence for pigs seemed to indicate that parallelism existed between Ab-C susceptibility and avirulence, except for strain 38, which was Ab-C susceptible yet virulent. There was agreement between virulence for mice and pigs, except for strains 10 and 61, which were avirulent for mice but relatively virulent for pigs. The 3 strain criteria under comparison (ie, Ab-C susceptibility, virulence for mice, and virulence for pigs) suggested only partial relatedness. Vaccination of pigs with the least virulent strain was found to protect them against challenge exposure with the most virulent strain, indicating that virulence factors may not be associated with immunogenicity. |
