Sores of boreal moose reveal a previously unknown genetic lineage of parasitic nematode within the genus Onchocerca
Fig 5
Representative histologic photomicrographs of moose skin collected between May and July 2021.
A. Skin biopsy taken before appearance of sores in May, 2021. There are small numbers of perivascular eosinophils and lymphocytes in the dermis. No pustules or microfilariae are observed. Hematoxylin and eosin, 200x magnification; insert: higher magnification of small numbers of eosinophils (black arrows) and lymphocytes. Hematoxylin and eosin, 600x magnification. B. Biopsy from a leg sore of a live adult female moose. There is a diffuse, severe infiltration with eosinophils throughout the dermis. Note the diffuse ulceration and a serocellular crust on the left. Hematoxylin and eosin, 40x magnification; insert: higher magnification of the eosinophilic infiltration. Hematoxylin and eosin, 600x magnification. C. Skin sample from a dead wild moose sampled in July, 2021. There is a diffuse, severe infiltration with eosinophils throughout the dermis. Note multiple intraepidermal pustules (dashed circle). D. Higher magnification of the pustule highlighted in C. The pustule is filled with eosinophils with a microfilaria in the center surrounded by degenerated eosinophils forming an eosinophilic sleeve. Hematoxylin and eosin, 600x magnification.