Forensic Diagnosis of Drowning in Animals: A Critical Review of Diagnostic Modalities and the Efficacy of the Diatom Test in Veterinary Medicine

Abstract

Veterinary forensic pathology is an interdisciplinary field that critically investigates animal mortality under suspicious or unlawful circumstances. Among various causes of death, drowning remains one of the most diagnostically challenging conditions due to its pathophysiological complexity and the lack of pathognomonic post-mortem findings. Drowning in animals typically results from submersion or immersion in liquid, leading to asphyxial death with distinct physiological consequences depending on the medium, either freshwater or saltwater. The post-mortem diagnosis of drowning is complicated by factors such as environmental contamination, autolysis, and the difficulty in distinguishing ante-mortem from post-mortem immersion. While classical diagnostic indicators, such as pulmonary oedema and frothy exudate, are frequently non-specific, the diatom test remains widely utilised in forensic investigation. However, environmental confounders and inconsistent protocols limit the technique’s reliability. This review critically evaluates current diagnostic methodologies for drowning in animals, including macroscopic, microscopic, and ancillary techniques, with particular attention to the diatom test and emerging technologies. It proposes an integrated diagnostic approach to enhance diagnostic accuracy and support judicial and animal welfare outcomes.

Keywords

Veterinary forensic pathology / Drowning / Forensic diagnosis / Diatom test / Hypoxia markers / Forensic microscopy / Animal mortality

Acknowledgments

This work would not have been possible without our colleagues’ invaluable discussions and paramount suggestions.

Author Contributions

Conceptualization, P.D., A.B. and S.K.; Investigation, P.D. and A.B.; Writing Original Draft, A.B.; Writing Review & Editing, P.D.; Supervision and Project Administration, S.K. All authors read and approved the final manuscript.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

No datasets were generated or analysed during the current study.

Funding

This work received no funding from internal or external sources.

Declaration of Competing Interest

The authors reported no potential competing interests. The authors declare no conflict of interest and confirm that all have contributed substantially to this work.

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