Influence of microbial inoculant on the oviposition and completion of life cycle of chrysomya megacephala and chrysomya rufifacies infesting rabbit carcasses

Abstract

Considering any surrounding factors as well as the cunning use of microbial inoculants to cover the smell of decomposing bodies could potentially alter (delay or speed up) the time of initial oviposition and developmental rate of insects infesting the corpses, thereby resulting in erroneous estimation of post mortem interval (PMI); such factors led to the initiation of this research. This research was conducted to assess the influence of a commercially available microbial inoculant (EM.1®) on the initial oviposition and developmental rate that lead to completion of life cycle of the two prevalent necrophagous flies (Chrysomya megacephala and Chrysomya rufifacies) in Malaysia infesting rabbit carcasses. In this research, nine rabbit carcasses were equally divided into control (C) and two treated (T1 and T2) groups. The T1 and T2 carcasses were individually sprayed with two different concentrations at 1:500 and 1:100 of the same microbial inoculant, respectively. The durations taken for each species of fly to first oviposit and complete their life cycle in treated carcasses were compared with that of control carcasses. Results revealed that single application of the microbial inoculant on both the treated carcasses did not statistically impede oviposition of both species as well as their subsequent developmental patterns (Kruskall-Wallis H: P > 0.05) when compared to the control carcasses. Since this is the first research that reported on the time of initial oviposition and completion of life cycle for C. megacephala and C. rufifacies in the presence of microbial inoculant, the results observed here may prove useful for estimating PMI in Malaysia particularly in cases where the use of microbial inoculant was suspected.