This study carried out on nine healthy exposed domestic rabbits (Oryctolagus cunicularis L.) and nine guinea pigs (Cavia porcellus L.) during winter and summer seasons 2012 in Cairo, Egypt. Animals divided into 3 groups. The first killed by tramadol, the second group killed by zinc phosphide, where the third group killed by asphyxia as a control experiment. Immediately after death, carcasses were transferred without delay to the study site. The carrions were visited daily, the decomposition process was observed, the invading insect species which collected from carcasses at each stage were identified by using special taxonomic keys, the insect's successive waves in different carcasses were noticed and the daily climatic data were recorded as well.