Diagnosis of Avian Tuberculosis in Swinhoe's Pheasants Using Conventional and Molecular-Based Techniques

Abstract

Avian tuberculosis was diagnosed via histopathology, microbiology, and molecular biology in two of six pheasants from a local sanctuary bird house in Taiwan. Swinehoe's pheasant (Lophura swinhoii) is a near-threatened species in Taiwan. The infected birds showed clinical signs such as fatigue, inappetence, diarrhea, and fluffing of feathers. On postmortem, nonmineralized caseogranulomas were present in the brain, heart, lung, liver, spleen, costal membranes, and intestinal tracts. The presence of granulomas in the lungs of the infected pheasants may suggest that exposure to the infective agent was via the respiratory route rather than the alimentary route. Histopathologic findings were typical of avian tuberculosis, including acid-fast bacilli and centrally located caseous necrosis surrounded by epitheloid macrophages, lymphocytes, and multinucleated giant cells. Laboratory confirmation was made based on lesions and via Ziehl-Neelsen acid-fast stain, polymerase chain reaction, nucleic acid sequencing, and a reliable assay protocol for identification of diseases bioactive amplification with probing assay.

Avian tuberculosis in a captive cassowary (Casuarius casuarius)

“…Avian tuberculosis is an infectious disease of all species of exotic, wild, and domestic birds, caused by Mycobacterium avium (5,7). It is a chronic debilitating disease that can persist for years in an infected flock.…”

Clinico-pathological features of tuberculosis due to Mycobacterium tuberculosis Uganda genotype in patients with tuberculous lymphadenitis: a cross sectional study

“…The material was gently spread on the second slide by pulling the two slides facing each other gently apart. For each aspirate four slides were prepared, one for Papanicolaou stain, two for acid fast bacilli (AFB) stain (Ziehl Neelsen and fluorochrome respectively) while one was air dried for Romanowski stain (Biostains, UK) using standard protocols [25,26]. Cytomorphological findings were recorded in terms of presence or absence of granuloma formation, necrosis, Langhans giant cells and epitheloid transformed macrophages [27].…”