Acid-fast bacterial infection in four turacos

Over a 10-year period (1986-1996), four turacos (Musophaga species and Tauraco species) at the North Carolina Zoological Park were diagnosed with acid-fast bacterial infections by histologic examination of postmortem tissues. In two turacos, the acid-fast bacteria were identified as belonging to the Mycobacterium avium-intracellulare complex. In the two other turacos, the acid-fast bacteria were not identified, but lesions were consistent with infection caused by Mycobacterium species. These four birds represented two-thirds of all turacos that died at this facility during the 10-year period. Clinical signs of mycobacterial infection in the turacos included the presence of soft tissue masses within the infraorbital sinuses, nasal turbinates, oral mucosa, cloaca, and abdominal musculature. On histologic examination, these masses were areas of granulomatous inflammation that contained numerous acid-fast bacterial rods. Infection with bacteria of the M. avium-intracellulare complex in two of the turacos was confirmed by radiometric culture in conjunction with a gene-specific DNA probe. Based on these findings, we recommend that mycobacteriosis should be considered as a differential diagnosis whenever soft tissue masses are identified in turacos.