Abstract
A 15-year and 7-month-old male European wolf kept in a zoological park since birth, became emaciated and died. At necropsy, the gastric and mesenteric lymph nodes were enlarged, and perforation was observed in the stomach. Histopathologically, diffuse proliferation of lymphoid tumor cells was observed in the lymph nodes, stomach, lungs, kidneys and spleen. The tumor cells were immunopositive for CD3, CD8, granzyme B, and TIA-1. These results suggest that the tumor cells exhibited a cytotoxic T-cell immunophenotype. Clonal rearrangement of the T-cell receptor gene was identified using standard canine primers. This is the first report on histopathological and immunohistochemical characteristics of T-cell lymphoma in a wolf, highlighting the potential effectiveness of a canine clonality analysis for diagnosing lymphoma in wolves.