Intra-Palpebral Tuberculin Skin Test and Interferon Gamma Release Assay in Diagnosing Tuberculosis Due to Mycobacterium caprae in European Bison (Bison bonasus)

Abstract

Despite the threat posed by tuberculosis (TB) to the protected European bison (Bison bonasus), no validated TB tests exist for this species. This pilot study evaluates two tests based on detecting cellular immunity for this purpose: interferon gamma release assay (IGRA) and tuberculin skin test (TST). Ten animals were subjected to ante-mortem and post-mortem examinations. IGRA was performed using a commercial test, and the comparative TST was performed in the eyelids. The lesions were assessed post-mortem and material was collected for mycobacterial culture. The isolated strains were subjected to genotyping. At post-mortem examination, five out of ten individuals demonstrated both tuberculous lesions and positive culture results (Mycobacterium caprae). Compared to the palpebral TST, the findings of the IGRA are easier to interpret when diagnosing tuberculosis in European bison.

Is serological monitoring a fit-for-purpose tool to assess the epidemiological situation of tuberculosis in the sylvatic species of European bison (Bison bonasus) in Poland?

“…The use of serological tests in tuberculosis control programmes may significantly improve the detection of infected herds. As demonstrated by the results, the TST is less effective in detecting tuberculosis-affected European bison than the IGRA ( 7 , 10 ). Additionally, the results of both tests did not overlap.…”

“…In cattle and American bison ( Bison bison ), a purified protein derivative (PPD) of bovine tuberculin is applied intradermally into the neck or caudal skin fold. In European bison, the site used most commonly is the upper eyelid ( 10 ) due to the thickness, pigmentation and hair cover of the skin of this species ( 19 ). Additionally, it facilitates assessment of the reaction to the tuberculin injection without a second immobilisation of the wild animal.…”

“…The standard ante-mortem tuberculosis tests include the tuberculin skin test (TST), interferon gamma release assay (IGRA) and microbiological isolation. However, the technical limitations of the available tests, which may produce false results in non-domestic animal species, are still an issue ( 10 ). The TST and IGRA are nevertheless officially validated examinations required for international movement of European bison or in suspected cases of BTB.…”

Review on Bovine Tuberculosis: An Emerging Disease Associated with Multidrug-Resistant Mycobacterium Species

“…European Bison ( Bison bonasus ) is extremely sensitive to mycobacterial infection and its ongoing restitution requires the improvement of ante-mortem diagnostic methods such as TST and IGRA [ 54 ]. The authors used an intrapalpebral and recommended the use of the two tests in parallel instead of relying on one method alone.…”

The eradication of M. caprae tuberculosis in wild boar (Sus scrofa) in the Bieszczady Mountains, southern Poland – an administrative perspective

“…Animal tuberculosis (TB) is a zoonotic disease caused by acid-fast bacteria belonging to the Mycobacterium tuberculosis complex (MTBC) ( 23 , 28 ). Of these, the main causes of tuberculosis in cattle, other livestock, companion animals, wild animals and even some species of carnivorous birds are Mycobacterium bovis and Mycobacterium caprae ( 1 , 4 , 13 , 14 , 28 ).…”