Experimental studies on the serological relationships between Yersinia enterocolitica and Brucella abortus.

Yersinia enterocolitica O9 was shown to provoke O, OH and H antibody response in calves. Brucella abortus failed to generate Yersinia H antibody response and generated Brucella O antibodies that cross-reacted with Yersinia O and OH antigens. The presence of Yersinia H agglutinins along with a higher titre of Yersinia OH antibody than Brucella O antibody is suggestive of subclinical infection with yersiniosis rather than brucellosis. Cross-absorption of sera from calves with established Yersinia infections indicated that absorption of sera with Brucella O antigens, although completely removing Brucella O antibodies, failed to remove completely Yersinia O, OH and H antibodies, and thus provides an additional method of distinguishing between the two infections.