Pathology of natural Mycobacterium bovis infection in European badgers (Meles meles) and its relationship with bacterial excretion

Sixteen European badgers (Meles meles) from three statutory removal operati ons were studied. Samples of tracheal aspirate, pooled lymph nodes and urin e were cultured for mycobacteria. Seven of the badgers were infected with M ycobacterium bovis and had tuberculous pulmonary lesions which varied in se verity from extensive granulomatous consolidation to microgranulomas which were not detectable grossly. Tuberculous lesions were also observed in the upper respiratory airways, intestines, kidneys, spleen, liver, thymus, pleu ra and lymph nodes. One badger had tuberculous bite wounds. The histopathol ogical characteristics of the tuberculous reactions and the associated tiss ue damage in various organs, together with the gross pathology, indicate th at both mildly and severely infected badgers have the potential to excrete M bovis by several routes.