Abstract
From August to November 2023, a disease outbreak occurred in a research colony of 33 mixed-sex, five-month-old central bearded dragons obtained from a private breeder in the USA. Clinical presentation consisted primarily of dehydration, lethargy, inappetence, weight loss, neck extension, sporadic open mouth breathing indicating dyspnea, and sudden death. A total of six deaths occurred during this period. Pathological investigation followed by molecular diagnostics and whole-genome sequencing revealed Mycoplasma pogonae as the cause of disease. Pneumonia (5/6) was diagnosed from necropsy. Types of pneumonia included histiocytic (1/5), combined histiocytic and lymphocytic (2/5), histiocytic and granulocytic (1/5), and heterophilic pneumonia (1/5). Our results confirmed that M. pogonae infection is associated with sudden mortality in a colony of captive central bearded dragons in the USA and that M. pogonae has a potential pathogenic role as a primary infectious agent.