EN
Histochemical assays were made to study the activity of the following respiratory enzymes: α-glycerophosphate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase, and cytochrome oxidase in tissues of Fasciola hepatica during the parasite’s development in the liver of the definitive host. The respiratory enzyme activity was assessed in the tegument, parenchyma, oral sucker, and in the caecum of juvenile and adult F. hepatica inhabiting the host’s liver parenchyma (infection week 1 to 4) and bile ducts (infection week 5-7), respectively. Changes in the intensity of the parasite’s reaction to the dehydrogenases studied were found to be habitat-dependent (liver parenchyma vs. bile ducts). No cytochrome oxidase activity was detected in F. hepatica tissues.