OBJECTIVE: To determine prevalence of tuberculosis caused by infection with Mycobacterium bovis in cervids on privately owned ranches in northeastern lower Michigan. DESIGN: Epidemiologic survey. ANIMALS: Cervids on 96 privately owned ranches. PROCEDURES: A combination of slaughter and skin tuberculin testing was used to collect data. Infection with M. bovis was confirmed by use of standard necropsy and bacteriologic culture techniques. RESULTS: Cervids with tuberculosis were detected on 1 of the 96 ranches. The apparent prevalence of tuberculosis in cervids from the 96 ranches was 1.1 cases/100 cervids (21 cases/1,867 cervids tested). For the ranch with infected cervids, prevalence of infection with M. bovis was 12.1 cases/100 cervids (21 cases/174 cervids tested). No obvious gross lesions were seen in 8 of 21 white-tailed deer and 1 coyote with culture-confirmed M. bovis infection. CONCLUSIONS AND CLINICAL RELEVANCE: The lack of visible lesions in a substantial proportion of infected animals should be taken into consideration in studies involving detection and prevalence of tuberculosis.
OBJECTIVE: To determine prevalence of tuberculosis caused by infection with Mycobacterium bovis in cervids on privately owned ranches in northeastern lower Michigan. DESIGN: Epidemiologic survey. ANIMALS: Cervids on 96 privately owned ranches. PROCEDURES: A combination of slaughter and skin tuberculin testing was used to collect data. Infection with M. bovis was confirmed by use of standard necropsy and bacteriologic culture techniques. RESULTS: Cervids with tuberculosis were detected on 1 of the 96 ranches. The apparent prevalence of tuberculosis in cervids from the 96 ranches was 1.1 cases/100 cervids (21 cases/1,867 cervids tested). For the ranch with infected cervids, prevalence of infection with M. bovis was 12.1 cases/100 cervids (21 cases/174 cervids tested). No obvious gross lesions were seen in 8 of 21 white-tailed deer and 1 coyote with culture-confirmed M. bovis infection. CONCLUSIONS AND CLINICAL RELEVANCE: The lack of visible lesions in a substantial proportion of infected animals should be taken into consideration in studies involving detection and prevalence of tuberculosis.