ABSTRACT The effects of subcutaneous injections of oxycodone hydrochloride to domestic pigs, Sus scrofa L., were examined with regard to postmortem insect successional patterns and the development of P. regina (Meigen) in the summers of 2006 and 2007 in Blacksburg, VA. Insect samples were collected from the carcasses of oxycodone treated and untreated pigs for 7 days postmortem during both studies. In total, 29 insect taxa were collected, with 29 and 23 taxa observed on the carcasses of oxycodone treated and untreated pigs, respectively. The earliest colonizers were dipterans in six families, with P. regina, Lucilia coeruleiviridis (Macquart), and Cochliomyia macellaria (Fabricius) being the most common. Beetles in 8 families were collected on treated pigs. Permutation analysis between successional patterns of insect taxa from carcasses of oxycodone treated and untreated pigs was used to compare successional pattern similarity. The results of the development study of P. regina maggots in vitro show no significant differences between the distributions in maggot length for larvae reared on liver or loin tissue from treated and untreated pigs. However, differences were detected in maggot length for the third instars feeding on treated loin tissue. Maggots that fed on tissue from oxycodone treated pigs took °Ö9.6 hours less to reach the pupal stage than maggots on control pigs. The shorter development time for maggots on tissue from oxycodone treated pigs was due to the shorter stadium of second and third instars.

KEY WORDS entomotoxicology, forensic entomology, successional pattern, development, Phormia regina