ARS | Publication request: DEER TO DEER TRANSMISSION OF MYCOBACTERIUM BOVIS

Submitted to: International Workshop on Tuberculosis in Animals
Publication Type: Abstract Only
Publication Acceptance Date: September 15, 1999
Publication Date: N/A

Technical Abstract: Tuberculosis caused by Mycobacterium bovis has recently been detected in free-ranging white-tailed deer (Odocoileus virginianus) in northeastern Michigan. Results of a 1998 survey indicate the prevalence of tuberculosis in this region to be 2.6%. To control tuberculosis in white-tailed deer, a better understanding of disease progression, transmission, and susceptibility to infection with M. bovis is necessary. Therefore, we developed a model of natural infection using intratonsilar inoculation of white-tailed deer with M. bovis. Using this model we investigated the ability of experimentally infected deer to transmit M. bovis to uninfected penmates. Two to three infected deer were housed with 2 uninfected deer (sentinels) in a pen where deer shared water and feeding sites. Bacteriologic culture of swabs from the mouth, nasal passages, and rectum demonstrated that experimentally infected deer shed M. bovis in nasal secretions, saliva, urine and feces. Mycobacterium bovis was also isolate from feed, likely contaminated by saliva or nasal secretions from infected deer. Sentinel deer were found to be infected and shedding M. bovis in saliva and feces by 42 days after commingling. Within 70 days of contact, uninfected deer converted from negative to reactor status as determined by the comparative cervical skin test (CCT) for Cervidae. These results suggest that during periods of close contact, infected deer readily transmit M. bovis to uninfected deer. In regions where infected deer are present, deer to deer contact, as well as contact with other animals should be minimized.