Agar gel immunodiffusion test (AGID) using the O-polysaccharide was compared with serologic tests used in brucellosis diagnosis in non-infected, infected and early vaccinated cattle with strain B-19, in order to differentiate vaccinal antibodies from those resulting of natural infection by Brucella abortus. None of the techniques can differentiate with absolute reliability the vaccinal antibodies from antibodies associated with natural infection to Brucella abortus. Moreover, the use of AGID with this objective would cause maintenance of infected animals in the herd.
Bovine; brucellosis; diagnostic; agar gel immunodiffusion test
