Retrospective classification of veterinary forensic cases from the archives of the Italian Istituti Zooprofilattici...

Definitive guidelines for the classification of cases in Veterinary Forensic Medicine (VFM) are currently unavailable. An attempt to classify lesions observed in forensic necropsies was proposed in 2022 following the codes of the ICD-11. The archives of the Istituti Zooprofilattici Sperimentali (IIZZSS) are structured to identify forensic pathology cases using pre-coded information only on wild animals' mortality and suspected animal poisonings at the time of acceptance. In contrast, other forensic documentation sources, including non-pre-coded necropsy diagnoses, require interpretation based on laboratory test results and accompanying expert opinions.

This study proposes the classification of previously unclassified VFM cases through a three-step approach: (1) data analysis, (2) review and classification of expert opinions by assigning labels corresponding to the main forensic topics, and (3) organization of diagnoses into categories and subcategories. Cases recorded in the database of the Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise between 2013 and 2023 were retrospectively evaluated.

A total of 1,221 non-coded cases with an expert opinion were identified. Among these, 405 cases (33.16%) were classified as potential Veterinary Forensic Cases and categorized into five macro-categories and 19 subcategories. The main cause of mortality differed according to animal type: injury was the most frequent cause in pets, attack in livestock, and unlawful killing in wildlife.

This classification approach enabled the identification and organization of previously unclassified VFM cases within the institutional database. Poisoning cases and wild animal deaths caused by vehicular collisions were excluded as they were already pre-classified. Therefore, the reported percentages refer only to this subset of cases and do not reflect the overall mortality rates in the region.