SURVEY OF FREE-RANGING ELK FROM WYOMING AND MONTANA FOR SELECTED PATHOGENS

From December 1991 through January 1995, a disease survey was conducte d on herds of free-ranging, hunter-killed elk (Cervus elaphus nelsoni) From three areas in proximity to Yellowstone National Park. (YNP), Wy oming (USA), after tuberculosis caused by Mycobacterium bovis was disc overed in a captive herd of elk in the area. Complete or partial sets of specimens from 289 elk collected between December 1991 and January 1993 were examined histologically; no mycobacterial lesions were obser ved. Lesions of tuberculosis were not detected in tonsils or lymph nod es of the head from an additional 99 hunter-killed, adult elk from one area (area 2) collected in January 1995. Neither M. bovis nor M. para tuberculosis were isolated from any of the specimens cultured. Antibod ies to Brucella abortus mere detected in serum samples from 0%, 1%, an d 1% of elk from three areas sampled (areas 1, 2, and 3), respectively . Brucella abortus biovar 1 was isolated from multiple tissues from on e seropositive animal from area 3. Larvae with morphology consistent w ith Dictyocaulus sp. were found in 12%, 14%, and 0% of fecal specimens tested from areas 1, 2, anti 3, respectively. Pasteurella multocida a nd Actinomyces pyogenes were isolated from a lung with purulent bronch opneumonia and abscesses.