Abstract
Tuberculosis caused by Mycobacterium bovis is endemic in the African buffalo (Syncerus caffer) population in the Kruger National Park and other conservation areas in South Africa. The disease has been diagnosed in a total of 21 free ranging or semi-free ranging wildlife species in the country with highly variable presentations in terms of clinical signs as well as severity and distribution of tuberculous lesions. Most species are spillover or dead-end hosts without significant role in the epidemiology of the disease. White rhinoceroses (Ceratotherium simum) are translocated from the Kruger National Park in substantial numbers every year and a clear understanding of their risk to manifest overt tuberculosis disease and to serve as source of infection to other species is required. We report the findings of experimental infection of three white rhinoceroses with a moderately low dose of a virulent field isolate of Mycobacterium bovis. None of the animals developed clinical signs or disseminated disease. The susceptibility of the white rhinoceros to bovine tuberculosis was confirmed by successful experimental infection based on the ante mortem isolation of M. bovis from the respiratory tract of one rhinoceros, the presence of acid-fast organisms and necrotizing granulomatous lesions in the tracheobronchial lymph nodes and the detection of M. bovis genetic material by PCR in the lungs of two animals.
Highlights
Bovine tuberculosis (BTB), caused by Mycobacterium bovis (M. bovis), is a chronic, progressive debilitating disease characterized by necrotizing granulomas in the lungs and lymph nodes in many free-ranging wildlife species, with clinical signs only visible in the later stages of the disease [1]
We describe the clinical features, hematological, biochemical and anatomical pathology induced in experimental M. bovis infection in three white rhinoceroses under captive controlled conditions
polymerase chain reaction DNA amplification (PCR) assays conducted on DNA extracted from 47 individual formalin-fixed paraffin-embedded (FFPE) tissues from PB1, PB2 and PB4 yielded specific DNA products (123 bp in size) from two lesions in the left lung of
Summary
Bovine tuberculosis (BTB), caused by Mycobacterium bovis (M. bovis), is a chronic, progressive debilitating disease characterized by necrotizing granulomas in the lungs and lymph nodes in many free-ranging wildlife species, with clinical signs only visible in the later stages of the disease [1] Susceptibility to this multi-host pathogen, transmissibility and impact of the disease at population level differ vastly between species, but are largely unknown for most wildlife species [2]. In 2009, localised incidental BTB lesions were reported in a semi-captive black rhinoceros (Diceros bicornis minor) in South Africa [8] and, in 2014, a semi-free ranging black rhinoceros was found dead with extensive lesions consistent with BTB from which M. bovis was isolated (M Otto, personal communication) These cases illustrate the potential for natural infection of rhinoceroses with this organism, no indication of clinical infection in free-ranging rhinoceroses exists and the health impact in free-ranging animals remains unknown
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call