Ultrasonographic Assessment of the Lungs in Asiatic Elephants (Elephas maximus).

Abstract

Asian elephants possess a unique pulmonary anatomy that presents challenges for diagnosing respiratory diseases, particularly when reared under human care where environmental stressors, poor hygiene and limited physical activity predispose them to respiratory pathologies. Conventional diagnostic tools such as radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are impractical for elephants due to their large body size. Diagnosis of lung pathologies is often delayed until postmortem. This study evaluated the diagnostic utility of lung ultrasound (LUS) as a noninvasive, real-time imaging modality in assessing lung health in Asian elephants. A total of 68 noncardiac transthoracic ultrasound scans were performed on 28 elephants to develop a systematic approach for pulmonary imaging. LUS demonstrated high sensitivity in detecting lung lesions, including interstitial syndrome, pulmonary edema, consolidation, pneumothorax, and pleural effusion, even in apparently healthy, asymptomatic individuals. Specific thoracic zones serving as acoustic windows were successfully mapped to improve consistency in lesion localization. Additionally, a semi-quantitative LUS score was developed for the objective assessment of lung aeration across 24 thoracic regions. Despite species-specific challenges such as narrow intercostal spaces and large lung volume, key sonographic features, including A-lines, B-lines, lung sliding, and bronchograms, were visualized. This study establishes LUS as a practical, field-adaptable tool for antemortem detection and monitoring of respiratory disease in elephants. Its ability to detect subclinical pathology offers significant benefits for early intervention, improved clinical outcomes, and support for conservation efforts. LUS has the potential to transform pulmonary diagnostics in elephant healthcare, bridging a critical gap in veterinary medicine for this endangered species.