Avian tuberculosis in a captured Ruppell’s griffon vulture (Gyps ruppellii): a case report

Avian tuberculosis was diagnosed in a captured female Ruppell’s griffon vulture (Gyps ruppellii) with granulomatous splenitis and hepatitis. At necropsy, whitish to yellow nodules of various sizes were found in the spleen and liver, and fibrinous coelomitis was present in the body cavity. Histopathologically, the granulomas appeared to be typical of avian tuberculosis. In some granulomas, necrotic centres surrounded by a variable layer of palisading epithelioid macrophages and multinucleated giant cells with variable admixture of lymphocytes and plasma cells were present. Signs of mineralization in granulomas were not observed. Using Ziehl-Neelsen staining the presence of acid-fast bacilli was demonstrated in organs affected by granulomatous inflammation. A diagnosis of Mycobacterium avium subsp. avium infection was confirmed by culture and quantitative Real-Time PCR examination for the presence of specific insertion sequences for avian tuberculosis (IS901 and IS1245) in the liver and spleen.