Effect of praziquantel on histopathology in experimental porcine schistosomiasis

Abstract

Indigenous piglets, 2-month old and of either, sex were infected each with 1500 cercariae of Schistosoma incognitum by tail method and were,divided into 2 groups. The first group was treated with praziquantel @ 25 mg/kg body weight on 21 st DPI while second group was kept to study infected untreated control. Additionally, 2 piglets from same litter were kept as un infected untreated healthy controL The animals were sacrificed on 47-52 DPI and studied for gross pathology; tissues were processed in acetone-benzene paraffin series and 5 µ sections were studied after staining with haematoxylin and eosin. Grossly, lungs of infected untreated animals showed hyperaemia and emphysema. The liver was enlarged, congested with grayish foci over the surface while severe congestion of mesenteric blood vessels was observed in the intestine. The treated animals showed either mild,or absence of these features. Microscopic studies revealed inflammatory reactions, distension and rupture of alveoli, hyperplasia of peribronchial lymphoid tissues in untreated infected animals while treated animals showed mild emphysematous changes with absence of peribronchial hyperplasia. The liver of infected untreated animals had perivascular infiltration and degenerative changes in the hepatocytes which were absent in the treated animals with subsiding inflammation in perivascular area. A chronic inflammation with sloughing of intestinal epithelium was observed in untreated, infected animals while no such reaction could be observed in treated animals.