The protective efficacy of viral vectors expressing immunodominant Brucella proteins Omp16, L7/L12, Omp19, and SOD at mono-, bi-, or tetravalent vaccine formulations was compared to that of a commercial vaccine B. melitensis Rev.1 and PBS and assessed by parameters, such as colonization of the virulent strain of B. melitensis 16M in the lymph nodes and organs of the vaccinated and unvaccinated animals and index of infection (number of tissues and organs from which Brucella bacteria were isolated). This evidence concerns the gene RPL7 and infection.