The Results of Active Immunization of Mice and Rats with Heat-Killed Vaccines of Br. Abortus and Br. Melitensis

In a previous communication Kolmer, Bondi, Howard and Rule' reported that rabbits given subcutaneous injections of a heat-killed vaccine of Br. abortus developed agglutinin, bacteriotropin and protective antibody in their serums which passively immunized a large percentage of mice against fatal infections following intra-abdominal inoculation with virulent strains of Br. abortus and Br. melitensis. Also that rabbits im-