Effect of humidity on postmortem changes in rats

Area of Science:

• Veterinary Forensic Science
• Histopathology
• Postmortem Interval Estimation

Background:

• Accurate postmortem interval (PMI) determination is vital in veterinary forensics.
• Autolysis, a postmortem process, affects PMI estimation, but its relationship with environmental humidity is poorly understood.

Purpose of the Study:

• To investigate the influence of varying relative humidity levels on the autolytic process in rat organs.
• To enhance the accuracy of PMI estimation in veterinary forensic cases by understanding humidity's role in autolysis.

Main Methods:

• Histopathological examination of heart, liver, and pancreas from 38 male rats.
• Exposure of tissue samples to controlled humidity levels (20%, 55%, 80%) at 22°C.
• Sample collection at multiple time points (0 h to 8 days) for analysis.

Main Results:

• Distinct autolytic patterns observed across different humidity conditions.
• Low humidity accelerated autolysis, causing nuclear pyknosis, cytoplasmic disintegration, and myofiber interruption.
• Specific organ changes included liver triad aggregation, pancreas cell fragmentation, and cardiac striation loss under varying humidity.

Conclusions:

• A clear correlation between autolytic progression and relative humidity was established.
• Findings provide a basis for developing more precise and predictable PMI estimation methods in veterinary forensics.
• Understanding humidity's effect on autolysis is crucial for accurate forensic case analysis.