Microscopic lesions suggestive of Marek's disease in a Black Francolin (Francolinus f. francolinus).

Microscopic lesions suggestive of Marek's disease were found in tissues from the exotic game bird Black Francolin (Francolinus f. francolinus). These lesions consisted of a solitary spherical mass near the syrinx, histologically composed of sheets of small pleomorphic lymphocytes and a few plasma cells. Lymphocytic cell infiltrates were also seen microscopically in cuffs around vessels of the brain, in the sciatic nerve, and in several visceral organs.