The Rose Bengal test or buffered Brucella antigen test is a rapid slide agglutination technique for detecting anti-Brucella antibodies in animal and human sera. The bacterial suspension is reactive with both IgG and IgM antibodies, with the former detected more early (sub-clinical infections) and for a longer period (chronic phase) than with the conventional tube procedure. The determination is made by assaying the buffered Brucella suspension (pH 3.6) colored with Rose Bengal against the test sera. The presence or absence of visible agglutination is indicative of the presence or absence of antibodies in the tested samples.
