Antemortem Diagnosis of Mycobacterium bovis Infection in Free-ranging African Lions (Panthera leo) and Implications for Transmission

Abstract

ABSTRACT:Diagnosis of tuberculosis in wildlife often relies on postmortem samples because of logistical challenges and lack of field-friendly techniques for live animal testing. Confirmation of infection through detection of infectious organisms is essential for studying the pathogenesis and epidemiology of disease. We describe the application of a technique to obtain respiratory samples from free-ranging living lions to facilitate detection of viable Mycobacterium bovis under field conditions. We identified M. bovis by mycobacterial culture and PCR in tracheobronchial lavage samples from 8/134 (6.0%) lions tested in Kruger National Park, South Africa. This confirms the respiratory shedding of viable M. bovis in living lions. The implications of these results are that infected lions have the potential to transmit this disease and serve as maintenance hosts.

Experimental Mycobacterium bovis infection in three white rhinoceroses (Ceratotherium simum): Susceptibility, clinical and anatomical pathology

“…Each pellet was resuspended in 1 ml PBS and 500 ul of this suspension was transferred to a Mycobacteria Growth Indicator Tube (MGIT ™ ) and incubated in a BACTEC ™ MGIT ™ 960 Mycobacterial Detection System (both Becton Dickinson). Lavage fluid was processed in a similar manner as previously described [22]. Cultures which were Ziehl-Neelsen stain-positive were identified to species by sequencing fragments of the 16S ribosomal DNA [23] and gyrB genes [24].…”

Felidae

“…Both captive and free-ranging felids are susceptible to tuberculosis due mycobacterial infections, mainly by Mycobacterium bovis (bTB). Disease has been described in free-ranging African lions, leopards, cheetah, Iberian lynx, and bobcat Briones et al, 2000;Bruning-Fann et al, 2001;Pérez et al, 2001;Aranaz et al, 2004;Cleaveland et al, 2005;Kirberger et al, 2006;Schmidbauer et al, 2007;Michel et al, 2009;Martinez et al, 2013;Miller et al, 2015). Wild African lions, leopard and cheetah are affected with the same spoligotype and variable number tandem repeat (VNTR) genotypes isolated from sympatric buffalo, while free-ranging lynx in Spain are infected with spoligotypes identical to those in cattle, wild boar and fallow deer.…”

Mycobacterium bovis infection in the lion (Panthera leo): Current knowledge, conundrums and research challenges

“…Aspiration liquid does not reach all areas of the lung and therefore can fail to recover viable organisms for culture (Somu et al 1995;Miller et al 2015) in infected lions. Additionally, processing (freeze-thaw) and transportation might also decrease viability of the samples.…”

“…Additionally, processing (freeze-thaw) and transportation might also decrease viability of the samples. Therefore prevalence of shedding of M. bovis is likely to be higher in the KNP population (Miller et al 2015). Infection in other organs or lymph nodes cannot be reached through BAL sampling, and sampling of these tissues requires biopsy (e.g.…”