Pathology of spontaneous Dictyocaulus sp. infection in hangul (Cervus elaphus hanglu), sheep and goat

Studies were conducted on spontaneous infection in hangul (Cervus elaphus hanglu) by a lungworm morphologically similar to Dictyocaulus viviparus, and spontaneous infection of Dictyocaulus filaria in a goat and six sheep on case-to-case basis. Representative samples from lung tissues, mesentary and bronchial lymph nodes were included in the study for histopathological examination. Changes occurring in the sheep and goat lungs in the study were similar and comparable. The lung pathology in goat and sheep was severe and characterized by the presence of severe alveolitis with epithelialization and hyaline membrane formation, peribronchiolar lymphoreticular follicles, severe infiltrative reaction against parasitic larvae with a preponderance of lymphocytes, macrophages, giant cells, eosinophils and plasma cells. The deer lungs showed occasional epithelialization and a variable cellular reaction comprising of scattered lymphocytes and scanty eosinophils around the parasites. Although parasites could not be demonstrated, large number of macrophages and plasma cell accumulations in the lymph nodes suggested a lymphogenous route of infection in all animals.