Gross and histopathological changes in lungs of Eurasian moose infected with Varestrongylus alces. 26, 27. Gross lesion seen from lung surface during gross examination (arrow), typical of varestrongylosis (26), and sectioned lesion (≈1.5 cm) (27). 28–31. Histological sections (H&E). 28. Part of the nodule is seen to the right, consisting mainly of large amounts of eggs, larvae and inflammatory cells, whereas normal, slightly emphysematous tissue is seen to the left. Scale-bar: 500 μm. 29. A close up of 28 showing to the left a large bronchiole (B) with epithelial hyperplasia and peri-bronchiolar lymphocytic inflammation that has large amounts of larvae in the lumen (area surrounded by arrowheads). To the right numerous eggs and larvae are filling up the alveolar space with rupture of alveolar septa and infiltration of inflammatory cells, mainly interstitially. Scale-bar: 500 μm. 30. Cross sections of adult nematodes (arrows) in the alveolar lumen surrounded by large amounts of eggs and some larvae with scattered multinucleated giant cells. Scale-bar: 100 μm. 31. First-stage larvae (arrows) partly engulfed and surrounded by giant cells (*), some macrophages and numerous eosinophilic granulocytes. Scale-bar: 50 μm.