The present study is conducted to investigate the effect of the flour mite extract namely Acarus siro on the small intestinal tissues. Eighteen female albino rats were orally intubated with 0.2 ml/g bw of the mite's extract 1day/week for 1, 2, and 3 months. The control group was orally intubated with 0.2 ml of the solvent (phosphate saline solution). Rats were dissected after treatment and the small intestines were removed and processed for histopathological study. The results showed histopathological lesions in the intestinal tissues such as necrosis and degeneration in the epithelial cells lining the villi, increase in the number and size of some goblet cells and focal degeneration in others, degeneration and atrophy in the crypt's cells, flatness in the villi and edema in the tissue, invasion of inflammatory cells and diffusion of mucous in the intestinal cavity. The present study indicates that prolonged ingestion of mite-contaminated foods causes various alterations in the small intestinal tissues of rats.
Key words: Flour mites, Acarus siro, histopathology, small intestine