MYCOBACTERIUM-AVIUM INFECTION IN A FARMED DEER HERD

Tuberculous lesions were identified over a 2-year period in 36 clinica lly normal red deer from a single herd. The lesions were only present in the retropharyngeal lymph nodes and lymph nodes draining the intest inal tract, indicating infection by the oral route. Mycobacterium aviu m was isolated from 27 of 29 lesions examined by bacterial culture. Gr ossly and histologically, the lesions were indistinguishable from thos e caused by Mycobacterium bovis. DNA restriction endonuclease analysis revealed that all the 26 M. avium isolates available for examination had identical cleavage patterns. These patterns were identical to a Ne w Zealand M. avium serotype 2 isolate from a pig and were very similar to a reference strain of M. avium serotype 2. The DNA examinations in dicated that the deer were infected from a common source that was not identified.