The Pourquier® Rose Bengale Ag is a suspension of Brucella abortus (Weybridge 99 strain) inactivated by heat and phenol and colored with rose bengal stain in an acidified buffer. It is calibrated according to the principle defined by the 64/432/EEC to give a positive reaction with a dilution at 1:45 of the second international anti-Brucella abortus serum (OIEISS), while with a dilution at 1:55 it should be negative.