In vitro studies on the effects of some anthelmintics on Cotylophoron cotylophorum (Digenea, Paramphistomidae): a structural analysis.

The effects of the anthelmintics praziquantel (PZQ), levamisole (LEV), mebendazole (MBZ), fenbendazole (FBZ) and albendazole (ABZ), on the morphology and the histology of a digenetic trematode, Cotylophoron cotylophorum, were studied. Scanning electron micrographs of the drug-treated worms revealed that PZQ was the most effective drug inducing surface damages to a great extent. The parasite exposed to PZQ for 6 h, showed smaller blebs on the oral sucker region as well as on the sensory papillae. These blebs enlarged in size after 24 h and ruptured after 30 h of exposure. The worms treated with LEV showed a few smaller blebs on the ventrolateral margin. In MBZ- and FBZ-treated worms the blebs appeared between the oral and genital sucker after 6 h of incubation. The changes were not apparent in the ABZ-treated worms.