Submitted to: International Conference on Mycobacterium bovis
Publication Type: Abstract Only
Publication Acceptance Date: 8/13/2000
Publication Date: N/A
Technical Abstract: Free-ranging white-tailed deer (Odocoileus virginianus) in northeast Michigan are recognized as a wildlife reservoir of tuberculosis caused by Mycobacterium bovis. Generally, animals become infected with M. bovis by inhalation of aerosolized organisms or by ingestion of organisms that are present in feed and water. Mycobacterium bovis has been isolated from saliva, nasal secretions, and tonsilar swab samples of experimentally infected white-tailed deer. Therefore, it is possible for infected deer to shed organisms in oral secretions and contaminate feed and water, which would then serve as a source of infection for other animals. Baiting of deer, which is allowed in Michigan, creates a situation where several deer eat from the same pile of feed and may contribute to transmission of tuberculosis. The purpose of this study was to determine how long M. bovis survives on various feeds when stored at different temperatures. The feeds examined were alfalfa hay, shelled corn, sugar beets, apples, carrots, and potatoes. Feeds were held at 22 C, 8 C, and -5 C for 2 hours, 1 day, 2 days, 3 days, and 7 days and 2 weeks, 3 weeks, 4 weeks, 8 weeks, 12 weeks, and 16 weeks. Mycobacterium bovis was isolated from all feeds stored at all temperatures for 7 days. At 8 C, M. bovis survives on all feeds except carrots for at least 12 weeks and at -15 C, it survives on all feeds for at least 16 weeks. Other experiments will be conducted to further examine the role of baiting in transmission of tuberculosis.