Eleven domestic guinea pig corpses were employed as models for studying decomposition, insect succession and determination of post-mortem interval (PMI) in Benha city, Egypt, from April 2009 to March 2010. Ambient temperature, faunistic succession over time, and the rate of decay in different seasons were all compared. Results indicated that ambient temperature is the chief factor determining the seasonal variations in decay rate. The diversity of insect community increased as the state of decomposition advances. Members of Dermistidae and Forrmicidae were the first coleopteran and hymenopteran colonizers in all seasons. Sarcophaga carnaria, Wholfortia magnefica and Chrysomya albiscepes were observed in spring, summer and autumn. Meanwhile, Wholfortia magnefica were absent in winter. Patterns of insect succession occurred in a predictable sequence that varied across different seasons. The rate of corpse's decomposition was faster in summer and autumn as compared to spring and winter. 3rd larval instar of Sarcophaga carnaria was selected as an indicator to estimate PMI using traditional (larval length, width and weight) and RAPD molecular techniques. Statistical analysis of traditional methods' results clarified that those methods were unsatisfactory and insufficient to be used for age determination, independently. Data analysis of randomly amplified polymorphic DNA (RAPD) polymerase chain reaction (PCR) technique demonstrated the suitability of these molecular markers to differentiate to some extent between the ages of 3rd larvae of Sarcophaga. |
