Abstracts (first author)
Deciphering the impact of Plasmodium parasites on bird odorant profile: what makes infected birds more attractive to mosquitoes?
It was recently demonstrated, using the avian malaria system (Plasmodium relictum SGS1 lineage), that infected birds are more attractive than non-infected birds to host-seeking Culex pipiens mosquitoes (Cornet et al. 2013 Ecology Letters). These results suggest that malaria parasites might manipulate bird traits that are used by mosquitoes to locate their host. This previous experiment eliminated visual or behavioural cues as potential signals, leaving olfactory cues as the most likely mechanism responsible for this enhanced attractiveness. To elucidate the proximal mechanisms of this fascinating manipulation, we characterised bird odorant profiles before and after a Plasmodium infection. The volatile organic compounds (VOC) emitted by hosts were captured on a solid phase (odour trap) using an innovative experimental setup. Gas chromatography was used for identification (mass spectrometry) and quantification (flame ionization detector) of VOCs. Cx. pipiens mosquito feeding preference (between infected and non infected birds) was simultaneously recorded following the protocol described in Cornet et al.. Here we correlate bird odour profiles and mosquito choice measurements, in order to identify VOC candidates susceptible to manipulation by Plasmodium parasites to render their hosts more attractive to mosquitoes.