NCJ Number
228527
Journal
Journal of Forensic Sciences Volume: 54 Issue: 5 Dated: September 2009 Pages: 1135-1140
Date Published
September 2009
Length
6 pages
Annotation
This pilot study was designed to collect empirical evidence on dipteran colonization attributable to twilight and nocturnal oviposition in Kelantan, Malaysia.
Abstract
This study found that colonization due to oviposition during the dawn, dusk, and night was limited and categorically delayed by about 2-3 days when compared with the colonization of the control baits exposed during the daytime. By the time freshly hatched maggots were observed in the dawn, dusk, or night cages, maggots in day-exposed cages had reached the second instar stage. Due to their larger size, it is these diurnally oviposited maggots that would be considered when estimating postmortem interval (PMI) under customary forensic practice. The novel approach of the current study, in which the same baits were exposed on consecutive days and nights, allowed nocturnal oviposition behavior to be studied during the course of decomposition as it would occur in case situations. These findings provide empirical evidence that in the climate of Kelantan, Malaysia, limited colonization due to nocturnal oviposition occurs in a decomposing bait only after the fourth or fifth day; however, due to diurnal oviposition, maggots colonize the bait on the second or third day. Such delayed and limited dipteran nocturnal oviposition is not a forensically significant phenomenon when estimating PMI, since the larger maggots derived from diurnal oviposition would be the ones considered when estimating PMI. Beef liver purchased from the local supermarket was used as bait to test the performance of the fly-proof cage. Bovine meat was used as bait for oviposition experiments. In addition to descriptions of materials used, this report describes the experimental setup, cage assignment and duration of bait exposure, and the periods of observation. 3 tables, 2 figures, and 28 references