[The antigenic relationship between Brucella abortus, Brucella melitensis and Yersinia enterocolitica serotype 0:3 and 0:9].

Antigenic interrelationship between B. abortus, B. melitensis, Y. enterocolitica serotype 0:3 and serotype 0:9 were investigated in hyperimmün sera obtained from rabbits, by using agglutination and agglutinin absorbtion tests. Agglutination was determined at 1/2560 titer of B. abortus and B. melitensis hyperimmün sera when their own antigens were used. On the other hand, these sera agglutinated Y. enterocolitica serotype 0:9 antigen at 1/1280 and 1/320 titer respectively. As it was seen that high level antigenic relation was found between B. abortus and Y. enterocolitica serotype 0:9 while antigenic resemblance was found at lower level between B. melitensis and Y. enterocolitica serotype 0:9. There wasn't any significant interrelationship between B. abortus, B. melitensis and Y. enterocolitica serotype 0:3. In conclusion it is though that it is impossible to distinguish B. abortus and Y. enterocolitica serotype 0:9 infections from each other by using agglutination tests when 0 antigens are used.