The Influence of the Physiological Stage of Lucilia Caesar (L.) (Diptera: Calliphoridae) Females on the Attraction of Carrion Odor

Abstract

In this study, the relationship between physiological conditions, including oogenesis and gravidity, and attraction to carcass odors was examined in order to discover how the attractivity of volatile organic compounds (VOCs) varied in females of the necrophagous fly Lucilia caesar (Linnaeus, 1758) (Diptera: Calliphoridae). Thus we want to shed some light on settlement behavior of scavenger flies. In bioassays with a decomposed mouse (Mus musculus), mixtures of synthetic compounds and flies of several physiological states, we observed rates of attraction and found compound classes that attract the different physiological stages. We found that a protein-poor diet increased the attraction to a carcass, especially between the age of 3 and 7 days. 7-day old females were attracted to cyclic compounds when mated and after exposure to a protein-poor nutrition, whereas they responded to fatty acids when mated after exposure to a protein-enriched diet. Furthermore we found that only with a protein-rich diet did the gonadal development complete with mature eggs in the Xth stadium between seven and 10 days and an overlapping second cycle with eggs in the Vth stadium at day 10.