An abattoir study of tuberculosis in a herd of farmed elk.

The purpose of this study was to examine the prevalence and distribution of grossly visible lesions of tuberculosis in a herd of 344 North American elk (Cervus elaphus) depopulated during a three-month period in 1991. Abattoir inspection detected mycobacterial lesions in 134 (39.8%) of the 337 animals received for slaughter. The prevalence of lesions increased with the age of the animals. Lesions were predominantly suppurative rather than caseous, and mineralization was less evident than in tuberculous lesions in cattle. Lesions occurred predominantly in lymph nodes, and lungs were the only organs in which mycobacterial lesions were found. The distribution of lesions suggested that aerosol transmission was the most significant means of spread of the disease within the herd. Giant liver flukes (Fascioloides magna) were observed in approximately 80% of the adult elk.