Pneumonia due to protostrongylid lung worms in wild himalayan bluesheep (Pseudoisnayaur)

History of frequent mortality of Himalayan blue sheep (Pseudoisnayaur) or bharal was reported in the region of Gangotri National Park (Uttarkashi, Uttarakhand). The carcass of an approximately 6 month old Himalayan blue sheep, recovered from above mentioned forest range was submitted for necropsy examination in the month of September 2017. Grossly, the carcass was emaciated with rough body coat and pale mucus membranes. Sub-pleural small to medium sized nodules were found in all lobes of both the lungs. Other organs did not reveal any significant gross pathological lesions. The tissue samples namely liver, lung, kidney, spleen and brain were fixed in 10% formalin and processed for histopathological examination. Relevant tissue samples were also collected on ice for microbial investigations. Significant histological changes were observed in tissue section of the lungs. Histological sections showed numerous cut portions of different parasitic stages including adult worms, larvae and eggs within the alveoli and bronchioles. These were surrounded by severe inflammatory reaction with infiltration of eosinophils and large mononuclear cells. The parasites in the lungs were identified as Protostrongylus rufescens. The present study puts on record the first case of verminous pneumonia in Himalayan blue sheep.