RESUMO
The time since death is an important aspect of forensic medicine; however, there is not an accurate single method to determine this data. Therefore, this research aimed to evaluate parameters and procedures based on the morphological analysis of cells and tissues to determine the time since death, using animal models. Pigs were chosen in this research because of their similarities with human anatomy, physiology, and pathophysiology. We identified the cells and tissue alterations in the viscera of pig cadavers according to the time since death, also describing the changes in the temperature of the organs and the bodies. The environmental temperature during the sample collection was also registered. The viscera analysis was performed for 24 h, with a 2-h variation period. After the sample collection, microscope slides were prepared for optical microscopy analysis. Through this 24-h analysis, we observed that the pancreas, small intestine, and large intestine presented more cellular alterations than the other organs. The alterations observed in the other viscera have significance when analyzed in combination. The meninges presented higher stability and few changes in 24 h, which could be relevant in an investigation of the time since death in a period greater than 24 h. Our results showed that histological evaluation is an excellent method to determine the time since death.