Comparison of insect colonisation in animal with and without fur

Forensic entomology is a branch of entomology used to solve mainly human criminal offences. In the last few years the entomological approach is more and more often applied in forensic cases involving animals or problems of a veterinary nature. Several studies on insect colonisation have been performed using pig (Sus scrofa) as a model for humans. Pigs and humans differ from the majority of the other mammals because of the lack of dense fur. Little information, concerning the effect of the fur on insect colonisation, is available. The aim of this pilot work is to investigate the effects of fur, season and fur*season on the colonisation of animal carrions by insects. Rabbits (Oryctolagus cuniculus) are used as a model for animals with fur. Five experiments have been performed during 2011 in a field in the neighbourhood of Modena (Northern Italy) (one in winter, one in spring, one in summer and two in autumn). For each test, two rabbits (2,5-4,5 Kg) have been used, one with fur and one without. The carrion without fur had been considered as control. Calliphora vicina, Lucilia sericata and Lucilia illustris have been the fly species collected. Hymenoptera parasitoids and larder beetles (Dermestes undulatus) have been also collected. No difference in the composition of the fly fauna colonizing the carrions has been detected in any of the performed experiments. In contrast, a delay in colonization of the animals with fur have been registered in all the experiments. This delay was bigger during the colder seasons. The fauna composition is clearly different comparing warmer and colder seasons. This data further confirms the different phenology of the genera Lucilia and Calliphora in Northern Italy.