Submitted to: Bovine Tuberculosis in Michigan Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 3/5/2001
Publication Date: N/A
Technical Abstract: To examine the distribution of lesions and bacterial infection, routes of potential shedding of bacteria, and environmental contamination with Mycobacterium bovis in a captive population of white-tailed deer with known M bovis infection, 116 captive white-tailed deer from a herd of approximately 300 deer located within a 1500-acre fenced facility were examined by thorough postmortem examination. Tissues with gross lesions suggestive of tuberculosis were collected separately for microscopic analysis and bacteriologic culture. Tissues from deer with no gross lesions were pooled for bacteriologic culture from regions of the head, thorax, and abdomen. Tonsilar, nasal, and oral swabs as well as fecal samples were collected from all deer for bacteriologic culture. Samples of hay and pelletized feed from feeding sites, soil around feeding sites, and water from 2 natural ponds used as watering sites by the deer were also collected for bacteriologic culture. Fourteen of 116 (12%) deer were tuberculous; however, only nine of 14 (64%) deer had lesions consistent with tuberculosis. Most commonly affected tissues included the medial retropharyngeal lymph node and lung. Five of 14 (36%) tuberculous deer had no gross lesions suggestive of tuberculosis; however, M bovis was isolated from pooled samples from the head. The mean age of tuberculous deer was 2.5 yr. with a range of 0.5 to 6 yr. Bacteriologic culture of swabs of the tonsilar crypt region yielded M bovis in 2 cases. Mycobacterium bovis was not isolated from any samples of pelletized feed, hay, soil, or water. State surveys for tuberculosis in deer generally involve examination of the head only.