Detection of food source by PCR analysis of the gut contents of Aldrichina grahami (Aldrich) (Diptera: Calliphoridae) during post-feeding period

The last meal of sarcophagous maggots may be useful in identifying the species on whose flesh they have fed (the"host" species). The DNA profile of the host species may indeed be detectable in the"last meal" . In this paper, mitochondrial DNA analysis of gut contents was used to identify the prior host of post-feeding larvae of Aldrichina grahami (Aldrich) (Diptera: Calliphoridae). A modified logistic equation was fitted to estimate the probability of identifying the host under five different constant temperatures (16, 20, 24, 28 and 32 o C). Our results shows that the detected time ranged from a maximum of 24 h at 32 o C to 42 h at 16 o C and a minimum of 12 h at 32 o C to 30 h at 16 o C. Furthermore, the host detection time was also calculated to give the maximal time after larval hatching from the egg. These results indicate that, in criminal cases where the maggots stray from the corpse, the last meal of the larvae should not be overlooked as potentially critical evidence.