SEROLOGIC RESPONSES IN DIAGNOSTIC-TESTS FOR BRUCELLOSIS IN CATTLE VACCINATED WITH BRUCELLA-ABORTUS 19 OR RB51

Serologic responses in the particle concentration fluorescence immunoa ssay and the card, complement fixation, and tube agglutination tests w ere measured for 10 weeks after vaccination of cattle with either Bruc ella abortus 19 or the lipopolysaccharide 0-antigen-deficient mutant, strain RB51. The responses of strain 19-vaccinated cattle were positiv e, whereas those of strain RB51-vaccinated cattle were negative, in al l of the tests. These results indicate that cattle vaccinated with str ain RB51 fail to produce antibodies that can be detected by convention al serologic tests that are used to diagnose bovine brucellosis.