The specification of pathomorphological changes occurring during Varestrongylus capreoli ontogenesis was studied on the basis of different forms of inflammation. The character, course and extent of inflammatory reactions were contingent on the maturity, localization and number of worms. The allergic inflammation accompanying the development of juvenile specimens inside the alveoli was followed by the regeneration of lung tissues providing suitable conditions for further development of the parasite. A prolonged edema occurring during the differentiation of juvenile parasites localized in the bronchioles caused a disposition of the roughen bronchial wall to its miliary necrotic disintegration producing a negative effect on further development of the helminth. The pathomorphological effect of mature productive parasites was characterized by focal changes hatching nodes. Activated epithelial cells of alveoli, phagocytizing disintegrating eggs and not developing 1st-stage larvae together with eosinophilic granulocytes participated in the restoration of the host lung functional ability while tolerating the presence of the parasite. A difficult excretion of sex products from the lungs stimulated the development of proliferative forms of inflammation reducing the number of Varestrongylus specimens.

Institute of Helminthology Slovak Academy of Sciences Kosice Czechoslovakia