| 摘要 |
Essentially pure H.paragallinarum organisms which on mutagenesis with a mutagenising agent give rise to mutant organisms of low or absent pathogenicity when compared to wild type reference strains, and mutants thereby produced are described. Particularly preferred H.paragallinarum organisms are strains HP286, HP19, HP286/10, HP286/15 and HP19/4. Vaccines containing H.paragallinarum organisms are also described. |
