RESUMEN
Brucellosis is caused by an intracellular pathogen Brucella melitensis. B. melitensis live in the phagocytic cells of the host. The major virulence factors of the brucellae are; a lipopolisaccharide cell wall antigen [endotoxin] and outer membrane proteins [OMPs] called OPP10, OMP 16, OMP19. In this study, the effect of brucellae or its endotoxins, on DNA and mitotics index was examined before and after treatment with Levafloxacin and doxycycline. All mice were divided equally into six experimental groups of ten mice each. Group one was control [no Brucella melitensis and no drugs], group two was inoculated intraperitoneally with x I0' CFU of Brucella melitensis [BM], group three was given BM and; levafloxacin i.p. 50 mg/kg/day for 30 days, group four was levafoxacin 30 days. Group five was given BM and Doxycycline oral 50 mg/kg/day 30 days, and group eight was given only Doxycycline 30 days. There were no significant differences in the average number of MN and MI between five groups and controls [p>0.05]. Neither B. melitensis, nor its outer membrane proteins and the antibiotics may not have any affect on micronucleus and mitotic index