Mycobacterium tuberculosis infection in two East African oryxes

Area of Science:

• Veterinary Pathology
• Mycobacteriology
• Zoological Medicine

Background:

• Tuberculosis (TB) is a significant infectious disease affecting various animal species.
• Oryxes, as exotic animals in zoological parks, can be susceptible to opportunistic infections.
• Early detection and diagnosis of TB in wildlife are crucial for herd health management.

Observation:

• Necropsy of two East African oryxes (Oryx gazella beisa) revealed tuberculous lesions.
• Microscopic examination identified granulomas with acid-fast bacilli in the lungs, liver, uterus, and mediastinal lymph nodes.
• The bacterium Mycobacterium tuberculosis was successfully isolated from affected tissues and mammary gland secretions.

Findings:

• The isolated Mycobacterium tuberculosis was confirmed as the causative agent of tuberculosis in these oryxes.
• Pathogenicity testing showed the isolate was virulent in guinea pigs but avirulent in rabbits.
• This case highlights the potential for Mycobacterium tuberculosis transmission within zoological collections.

Implications:

• This study underscores the importance of diagnostic surveillance for tuberculosis in zoological collections.
• Understanding the pathogenicity of Mycobacterium tuberculosis strains is vital for risk assessment and control strategies.
• Findings contribute to the knowledge base for managing infectious diseases in exotic ungulates.