In the wake of increasingly frequent bushfires emerging as a threat to wildlife worldwide, koalas have notably been the most rescued species in Australia. However, our understanding of burns and their severity in koalas is limited; hence, this study investigated the histopathological features and depth of burns in koala skin, as well as the presence of smoke-induced respiratory tract damage. In four bushfire-affected koalas that had been euthanised on welfare grounds, skin burns in various body regions were scored based on clinical appearance as superficial, partial thickness, or full thickness. Histological sections of affected regions of skin were assessed as Grades I–IV and showed that furred regions on the ear margins and dorsum were histologically more severe, at Grade III, compared with the clinical score. There was a similar finding for footpad burns, which were the most common body region affected. In the respiratory tract, pulmonary oedema and congestion were evident in all koalas. Overall, the results highlight that cutaneous burn lesions on furred and palmar/plantar surfaces can have higher severity based on the burn depth than is clinically apparent. Therefore, there is a need to consider this when developing treatment plans and establishing prognosis for burnt koalas at triage, as well as that a high likelihood of pulmonary oedema exists.

Abnormal vertebral column curvature is sporadically reported in koalas of the Mount Lofty Ranges, South Australia. This study evaluates the imaging features of 23 koalas from the Mount Lofty Ranges presenting with abnormal vertebral column curvature between 2015 and 2023 using digital radiography and computed tomography (CT). All images were evaluated by four reviewers to assess curve morphology, severity and Cobb angles for both scoliosis and kyphosis. For Cobb angle measurement, radiography performed similarly to CT with good agreement as measured by intraclass correlation coefficient (0.835 and 0.825 respectively) and Lin’s concordance correlation coefficient (>0.85). The apex vertebra was always located between T7 and L6. For both scoliosis and kyphosis apex vertebrae, the thoracolumbar region was the most common location (8/22 and 9/19, respectively). For scoliosis, the caudal thoracic and lumbar regions were equally common (7/22 each), whereas for kyphosis, the caudal thoracic region (7/19) was more frequent than the lumbar region (3/19). Vertebral body rotation was a common component particularly in severely affected individuals, in which complex or ‘S’ shaped curves also occurred. Severity ranged from minimal or mild (6/23) to moderate (5/23) and severe (12/23), with simultaneous kyphosis and scoliosis present most frequently (21/23). As a result, the term, kyphoscoliosis is the most appropriate morphological description for abnormal vertebral curvature in koalas and may have pathophysiologic commonalities with human idiopathic scoliosis. This study is the first to describe imaging features of abnormal vertebral column curvature in koalas and evaluate inter-modality and interobserver agreement between radiography and CT.