Histopathological changes caused by the nymph stage of Linguatula serrata in the mesenteric lymph nodes of goats.

Linguatula serrata (Fröhlich, 1789) is a ubiquitous parasite species belonging to pentastomids, which has been reported frequently from domestic herbivores of Iran. This study was carried out to elucidate the pathological changes caused by the nymphal stage of L. serrata in the mesenteric lymph nodes (MLNs) of goats. Jejunal and ileal MLNs of slaughtered goats infected with L. serrata were collected and fixed in 10% neutral formal saline. Histopathological changes included follicular necrosis accompanied by a loss of lymphocytes and oedematous cystlike spaces. Granulomatous lesions were formed by mononuclear cell infiltration and necrotic tissue. Some lymphocytes were apoptotic with chromatolysis. A more frequent vascular abnormality was vasculitis. These findings show that larval migration is the main factor to initiate trauma and cause irritation in the MLNs of goats. Since goats are habitual intermediate hosts in Iran, rigorous inspection of the MLNs of slaughtered goats is recommended in order to decrease the chance of human infection through the consumption of raw visceral organs of goats.