Histopathological study of Salmonella typhimurium infection in laboratory mice by using the light and electron microscope

Abstract

This study was designed to evaluate the histopathological changes for internal       organs of white female mice after inoculation with Salmonella typhimurium in dose 1x10⁸.Sixteen white mice apprrximatly age (one-two months) and body weight were (25-30) gram divided into 2 equal groups. The first group was inoculated with Salmonella typhimurium orally and   killed after24hr.Group2 was inoculated with normal saline as control group. The histopathological changes of the liver were showed  infiltration of kupffer cells and aggregation of mononuclear cells around the central vein with congestion of blood vessels and infiltration of inflammatory cells. The intestinal changes showed hyperplasia of goblet cells and infiltration of inflammatory cells in the lamina propria of atrophic villi. The results of the electron microscope were showed   S. typhimurium   lie close to the brush border of the villi of ileum of infected mice, and in another section noticed degeneration of the brush border and the apical cytoplasm with cavity formation occurs near a bacterium (arrow).  In addition,budding, swelling and elongation of microvilli are evident.In summary to the above, the microorganisms Salmonella typhimurium have the ability to infect ileum and penetrate to other internal organs.