Comparative developmental effects of tramadol hydrochloride and cypermethrin on Chrysomya albiceps (Weid.) (Diptera: Calliphoridae) reared on rabbit carrions

Abstract

This study compares effects of cypermethrin (a pyrethroid pesticide) and tramadol hydrochloride (an opioid) on the development of Chrysomya albiceps (Diptera: Calliphoridae) reared on intoxicated rabbits (Orctylagus cunicunus) carrions (injected intra-veinously with 4ml of the toxins, being a dosage always witnessed in drug abusive cases. The larvae body lengths were measured with a pair of compass and a transparent meter rule while the body weights were measured with Mettler Toledo weighing balance with sensitivity of 0.000 -1g. The mean maximum length and weight (Mean±SD): cypermethrin (06.77±0.03mm and 0.0056±0.0001g), tramadol (14.02±0.12 mm and 0.0123±0.0002g), and the control (10.50± 0.16mm and 0.0095±0.0001g) were reached at 96 hours after eggs were laid. However, the mean total developmental (from egg to adult C. albiceps) period was highest at 380.28±1.35hrs (15.8 days), 330.05±1.50 hours (13.8 days) and 281.2±1.20 hours (11.7 days) respectively for cypermethrin, tramadol hydrochloride and controlled groups. The results showed Post Mortem Interval (PMI) estimation errors of about 4 and 2 days respectively, when cypermethrin (pesticide) and tramadol hydrochloride (opioid) toxins used are compared with the control group of C. albiceps. Therefore, caution is required in the interpretation and application of insects’ data in forensic entomology when drugs and toxins are the suspected cause of death.

Keywords: Entomotoxicology, Post Mortem Interval, Chrysomya albiceps, opioid, forensic entomology, carrions