Abstract
Preventation of equine paratyphoid has been studied by many researchers, and variouskilled vaccines have been used, FIIRATO, and his associates, applied the AND0S chrometreatment [0 the preparatronr Of the vaccnne, and thC) reported that the chrome vaccine wasless toxic than the other killed vaccines, but that it caused abacterial suppuration after theintracutaneous injection, in the horse.The present studies of the chrome treatnnent were examined to remove the abovedrawback of the chrome vaccine, and the following results were obtained.1) Toxicity : Toxicity of the vaecirte was reduced by the chrome treatment with 8%chrome salts, as well as by 0.2% chrome salts.2) Suppuration : While forrnalin vaccine and O.2% chrome vaccine produced severeabacterial suppuration at the injection site, 8% chrome vaccine produced little or no suppura.tion but only a little induration.3) Antibody production : 8% chrome vaccine seemed to produce almost the samelevel of arrtibody later than did O.2% chrome vaccine, or formalin vaccine, irn rnice.
