title: Comparison of sampling methods, culture, acid-fast stain, and polymerase chain reaction assay for the diagnosis of mycobacteriosis in ring-neck doves (Streptopelia risoria).
abstract: Even when different diagnostic modalities are available, mycobacteriosis is difficult to diagnose in a live bird. To investigate the diagnostic value of sampling different tissues and using different diagnostic methods, we evaluated results of mycobacterial culture, Ziehl-Neelsen (ZN) staining, and single-amplification polymerase chain reaction assay (PCR) of 18 ring-neck doves (Streptopelia risoria) with confirmed natural infection with Mycobacterium avium avium. Results of testing liver biopsy, duodenal aspirate, and bone marrow aspirate samples and liver and spleen samples collected at necropsy were compared. Results showed the use of one single technique did not allow identification of all infected birds. In liver biopsy and bone marrow aspirate samples, culture had the highest sensitivity, whereas PCR assay and ZN staining had low sensitivity, and their combination was less sensitive than culture alone. Examination of ZN staining of the intestinal aspirate samples failed to detect infection in most birds. More splenic lesions contained acid-fast organisms than did liver lesions, suggesting that splenic biopsy may have the greatest potential for diagnosis of mycobacterial infection antemortem. Sensitivity was higher for postmortem examination of multiple liver sections than of a single biopsy section; therefore, obtaining multiple liver biopsy sections may increase detection of mycobacteria. Examination of multiple tissues and the use of several different diagnostic techniques significantly increases the probability of diagnosis of mycobacteriosis.
authors.affiliation: Schubot Exotic Bird Health Center, Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, 4467 TAMU, College Station, TX 77843-4467, USA.
authors.forename: Miguel D
authors.initials: MD
authors.lastname: Saggese
authors.forename: Ian
authors.initials: I
authors.lastname: Tizard
authors.forename: David N
authors.initials: DN
authors.lastname: Phalen
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques / Q000662:veterinary*; D010856:Columbidae; D009162:Mycobacterium avium; D016133:Polymerase Chain Reaction / Q000662:veterinary*; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000662:veterinary; D014379:Tuberculosis, Avian / Q000175:diagnosis*