Naturally Occurring Tuberculosis Caused By Mycobacterium Bovis in Brushtail Possums (Trichosurus Vulpecula) .2. Pathology

The gross and microscopic lesions due to Mycobacterium bovis infection are described in 73 brushtail possums (Trichosurus vulpecula) from population studies and from 11 terminally ill possums. Subcutaneous lesions were suppurative in nature, often discharging through sinuses to the exterior. Histologically, the smallest lesions comprised focal aggregations of macrophages with angulated cytoplasmic boundaries occasionally containing acid-fast organisms. Larger lesions were pyogranulomatous, with extensive necrosis, caseation and large numbers of intra- and extra-cellular acid-fast organisms. Few multinucleate giant cells were seen and fibroplasia was rare. Mineralisation was recorded in tuberculous lymph nodes from only two possums. Histological evidence of haematogenous and lymphatic spread was seen in some cases.

Author M. M. Cooke, R. Jackson, J. D. Coleman and M. R. Alley
Year 1995
Secondary title New Zealand Veterinary Journal
Volume 43
Number 7
Pages 315-321