Isolation and molecular characterization of Mycobacterium bovis causing pulmonary tuberculosis and epistaxis in a Thoroughbred horse

Abstract

Background: Tuberculosis caused by Mycobacterium bovis (M. bovis) is very uncommon in horses worldwide. Case presentation: In the current study, an eight-year-old male Thoroughbred in good body condition was admitted to the Equine Clinic at the Onderstepoort Veterinary Academic Hospital in 2005 due to bilateral epistaxis accompanied by coughing. Routine examinations were conducted to determine the cause of the condition. Endoscopic examination revealed the major source of the epistaxis as the trachea, whereas thoracic radiography indicated the presence of a primary pulmonary mass. M. bovis was isolated from a broncho-alveolar lavage (BAL) sample collected. The pulmonary mass reduced in size three months later following an oral administration of enrofloxacin (7.5 mg/kg PO SID). Genetic fingerprinting by spoligotyping identified the M. bovis isolate as spoligotype SB0868 strain. This M. bovis strain type was never described previously in South Africa (SA). This is the first case of M. bovis infection in a horse in SA which has been fully documented including clinical findings, isolation and genetic characterisation of the causative pathogen. Conclusions: This report indicates that horses may contract and harbour M. bovis despite their lower susceptibility compared to other domestic animals. It also suggests that the infection may be more easily contained and eliminated from the host.

<p>Chronic Wasting Disease In Cervids: Prevalence, Impact And Management Strategies</p>

“…The four CWD management strategies used in North American free-ranging wild deer include 1) general, non-selective population harvest (spatially targeted); 2) selective or targeted removal of clinical suspects (infected deer); 3) seasonal harvest (eg, summer) and 4) vaccination 144. Predictive models that evaluated these management strategies found that increased general hunting pressure with or without targeted sex group, the role of large predators, and seasonal hunting had some positive effect on CWD under specific conditions 145–147.…”

Mycobacterial infections in equids: Clinical characteristics and diagnostic techniques

“…Pulmonary infections may cause coughing, pyrexia and epistaxis if there is a single tuberculous granuloma (Hlokwe et al . ), whereas secondary miliary pulmonary infiltration results in chronic weight loss, sternal oedema, dyspnoea, nasal discharge and exercise intolerance (Lyashchenko et al . ).…”

“…; Hlokwe et al . ) and may present a greater zoonotic risk to personnel in close contact than the intestinal form.…”

Granulomatous Rhinitis in a Horse due to Mycobacterium intracellulare Infection

“…due to infection with M. bovis (Sarradell et al, 2015;Hlokwe et al, 2016), infections by M. avium are considered the most common cause of equine mycobacteriosis (Pavlik et al, 2008;Sano et al, 2014). Within the MAC complex, infections with M. avium subsp.…”

“…Horses are relatively resistant to infection with mycobacteria (Pavlik et al, 2004;Sarradell et al, 2015). Mycobacterial infections in horses are caused by members of the MTC, particularly M. bovis (Sarradell et al, 2015;Hlokwe et al, 2016), or by members of the MAC, particularly M. avium subsp. avium (Pavlik et al, 2008;Ryhner et al, 2009).…”