HISTOTAPHONOMIC DETERMINATION OF DECAY RATES AND POST- MORTEM INTERVAL OF SUS SCROFA LIVER USING SPECIAL STAINS

Abstract Accurate estimation of the post-mortem interval (PMI) remains a central challenge in forensic science, particularly in the early and intermediate stages of decomposition where conventional methods may lack precision. This study investigates the histotaphonomic alterations in the liver of Sus scrofa (domestic pig) as a model for human decomposition, with the aim of determining decay rates and improving PMI estimation using special histological stains. Fresh liver samples were obtained from healthy Sus scrofa specimens and subjected to controlled environmental conditions to simulate post-mortem changes over predetermined time intervals. Tissue samples were collected at regular intervals and processed for histological examination using routine Hematoxylin and Eosin (H&E) staining alongside special stains such as Periodic Acid–Schiff (PAS) for glycogen content, Masson’s Trichrome for connective tissue integrity, and Sudan Black B for lipid preservation. Microscopic evaluation focused on progressive cellular and structural changes including hepatocyte degeneration, nuclear pyknosis, karyorrhexis, sinusoidal collapse, autolysis, and microbial infiltration. Results demonstrated a time-dependent pattern of histological degradation. Early post-mortem intervals were characterized by mild cellular swelling and glycogen depletion, as evidenced by reduced PAS reactivity. Intermediate stages showed pronounced nuclear fragmentation, cytoplasmic vacuolation, and breakdown of hepatic architecture. In later stages, there was extensive tissue disintegration, loss of staining affinity, and increased bacterial colonization. Special stains proved valuable in highlighting specific biochemical and structural changes that correlated consistently with elapsed time since death. The study concludes that histotaphonomic analysis of Sus scrofa liver using special stains provides a reliable and reproducible method for assessing post-mortem changes. These findings support the application of liver histology as a supplementary tool in PMI estimation, particularly when combined with other forensic indicators. This approach enhances the accuracy of forensic investigations by offering measurable, time-dependent microscopic markers of decomposition.