The Succession Pattern and Development of Predominant Species of Blowflies to Suitcase-enclosed Rabbit Carcasses on Outdoor Versus Indoor Sites

Abstract

Introduction: Blowfly succession on animal carcasses aids in estimating the minimum post-mortem interval of decomposed bodies. However, colonization differs in cases where the decomposing bodies are enclosed. This study examines blowfly succession on enclosed rabbit carcasses to establish patterns relevant to forensic investigations. Materials & methods: Fifteen domestic rabbit (Oryctolagus cuniculus) carcasses were divided into three groups; enclosed indoors and outdoors, and exposed outdoor carcasses. Each carcass was placed in a suitcase as the mode of enclosure. Entomological and environmental data were observed and recorded. Results: Enclosement of the carcasses have altered the insect succession pattern during carcasses decomposition. Four species of calliphorid flies were identified on control carcasses, compared to only two species were found on enclosed carcasses. However, both groups of carcasses were colonised by two main blowfly’s species; Chrysomya megacephala (51.4%) and Chrysomya rufifacies (33.5%). The enclosement has caused delayed in oviposition which took around 49-76 and 50-77 hours for Ch. megacephala and Ch. rufifacies respectively. During fly development, longer eclosion time was also observed in Ch. megacephala (142.5-147.5 hrs) and Ch. rufifacies (162.5-169 hrs) compared to exposed carcasses (96-97 hrs). Consequently, the carcasses enclosure disrupted the normal blowfly’s oviposition and development, thus affecting the minPMI estimation. Conclusion: The enclosement of carcasses significantly altered blowfly succession, delayed oviposition, and prolonged the developmental time. These findings highlight the impact of physical barriers on blowflies succession and colonization of decomposing carcass in forensic investigation, emphasizing the need to consider the effect of enclosure when estimating the minimum post-mortem interval.