Improving diagnostic success in stranded dugong necropsy investigations https://doi.org/10.12982/VIS.2026.072
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Abstract
Stranding events of dugongs (Dugong dugon) provide important opportunities to investigate causes of mortality and population health in the wild. However, successful determination of the cause of death is often constrained by carcass condition and the availability of diagnostic investigations. This study aimed to evaluate factors influencing diagnostic success in stranded dugongs recovered along the Andaman Sea coastline of southern Thailand. A retrospective analysis was conducted using data from a centralized stranding database covering the period 2019 to 2025. A total of 166 stranding records were reviewed, of which 81 carcasses met the criteria for necropsy based diagnostic evaluation after excluding cases lacking examination or affected by advanced decomposition. Necropsy findings, histopathological results, and ancillary diagnostic investigations, including parasitological examination, bacteriological culture, and molecular detection of infectious agents, were compiled for each case. Diagnostic outcomes were categorized into four levels of certainty: undetermined cause of death, presumptive cause of death, tentative diagnosis, and final diagnosis. Overall, 26 cases (32.1%) achieved a final diagnosis, while 11 cases (13.6%) were classified as tentative diagnoses, 21 cases (25.9%) as presumptive causes of death, and 23 cases (28.4%) remained undetermined. Diagnostic resolution improved in later years of the study, with a declining proportion of undetermined cases. Trauma, parasitic disease, infectious disease, and systemic disorders represented the major pathological categories identified. Statistical analysis showed that mild to moderate carcass autolysis and detection of infectious agents tended to increase diagnostic success, whereas female sex and higher body condition score showed the opposite trend, although none of these associations were statistically significant. These findings highlight the importance of carcass condition, systematic necropsy procedures, and ancillary diagnostic investigations in improving cause of death determination in stranded dugongs and supporting effective conservation and health surveillance efforts
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