ABSTRACT
The mutagenic effect of Rift Valley fever [RVF] virus was tested in male mice bone marrow cells. Three virus titers were chosen [low [L], intermediate [IM] and high [H]]. These were 3, 300 and 3000 VP/dose, respectively. Mice were inoculated with each titer and samples were taken 24 and 48 hours later from bone marrow. An increase in chromosomal aberrations [structural and numerical] was observed in some treatments with RVF virus. The significant structural chromosomal aberrations are in the form of gape and centromeric attenuations, while the numerical aberration was endomitosis. All treatments showed a decrease in mitotic index [number of dividing nuclei per 300 cells], this decrease was highly significant. Although, the number of micronucleated PCE increased after inoculation with all treatments, the increase was below the significant level. Since there is no information available on the mutagenicity of RVF virus, more cytogenetic studies are suggested, the result of which could be compared with these results. This may throw some light on the mutagenic effect that could be produced by RVF virus