Pathology of Mycobacterium bovis infection in wild meerkats (Suricata suricatta)

Pathological lesions associated with Mycobacterium bovis infection (bovine tuberculosis; bTB) in free-living meerkats (Suricata suricatta) in the Kalahari Desert of South Africa are described. The pathology of bTB in meerkats was determined through detailed post-mortem examinations of 57 animals (52 meerkats showing clinical signs of bTB, and five not showing signs of disease). Lymph nodes and tissue lesions thought to be associated with bTB were cultured for mycobacteria. All 52 bTB-infected meerkats showed gross or microscopical granulomatous lesions, but M. bovis was cultured from only 42% (22/52) of these animals. The majority (96%, 50/52) of diseased meerkats had lesions in multiple sites, the pattern of which suggested haematogenous spread of M. bovis infection in this species. The histological characteristics of the tuberculous lesions, together with the gross pathology and the wide range of body systems affected, indicate that infection in meerkats is acquired principally via the respiratory and oral routes, whereas excretion is most likely via the respiratory tract and suppurating skin wounds. Urine and faeces appear to be unlikely sources of infection. The findings of this study provide information on the transmission, pathogenesis and epidemiology of bTB in meerkats that is likely to be relevant to the understanding of M. bovis infection in other social mammal species such as the European badger (Meles meles).