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Brucella melitensis is the most virulent species of Brucella affecting a wide range of livestock and humans. Sheep and goats are the classic and preferred hosts for B. melitensis. False positive reactions in serodiagnosis reduce the efficiency of diagnosis and hamper monitoring and eradication programs to brucellosis. Thus, there is a demand to identify immunogenic proteins which could be used as antigen in highly specific serological tests to detect Brucella infection in sheep and goats. In the present study nine immunodominant proteins from whole cell lysate of a Brucella melitensis field strain isolated from sheep were detected by immunoblotting and identified by MALDI-TOF mass spectrometry. The identified proteins are: superoxide dismutase, copper/zinc binding protein; chain A, Cu/ZN superoxide dismutase; 19 kDa periplasmic protein; transaldolase; fructose-6-phosphate aldolase; rhizopine-binding protein; hydrolase; 31 kDa cell surface protein and a hypothetical protein. These proteins showed immunoreactivity against positive antisera from sheep and goats naturally infected with Brucella, but failed to have immunogenicity towards negative antisera. Therefore, it would be of great value to further validate these proteins as novel specific candidates for serodiagnosis of brucellosis in small ruminants.