| Title: | Is Anopheles gambiae attraction to floral and human skin-based odours and their combination modulated by previous blood meal experience? |
| Author(s): | Kemibala EE; Mafra-Neto A; Saroli J; Silva R; Philbert A; Ng'habi K; Foster WA; Dekker T; Mboera LEG; |
| Address: | "Ministry of Health, Community Development, Gender, Elderly and Children, Vector Control Training Centre, P.O. Box 136, Muheza, Tanzania. elisonmwebembezi@gmail.com. University of Dar es Salaam, Dar es Salaam, Tanzania. elisonmwebembezi@gmail.com. ISCA Technologies, 1230, West Spring St, Riverside, CA, 92507, USA. University of Dar es Salaam, Dar es Salaam, Tanzania. Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA. Department of Entomology, The Ohio State University, Columbus, OH, USA. Swedish University of Agricultural Sciences, Alnarp, Uppsala, Sweden. BioInnovate AB, Lund, Sweden. SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania" |
| DOI: | 10.1186/s12936-020-03395-2 |
| ISSN/ISBN: | 1475-2875 (Electronic) 1475-2875 (Linking) |
| Abstract: | "BACKGROUND: Mosquitoes use odours to find energy resources, blood hosts and oviposition sites. While these odour sources are normally spatio-temporally segregated in a mosquito's life history, here this study explored to what extent a combination of flower- and human-mimicking synthetic volatiles would attract the malaria vector Anopheles gambiae sensu stricto (s.s.) METHODS: In the laboratory and in large (80 m(2)) outdoor cages in Tanzania, nulliparous and parous A. gambiae s.s. were offered choices between a blend of human skin volatiles (Skin Lure), a blend of floral volatiles (Vectrax), or a combination thereof. The blends consisted of odours that induce distinct, non-overlapping activation patterns in the olfactory circuitry, in sensory neurons expressing olfactory receptors (ORs) and ionotropic receptors (IRs), respectively. Catches were compared between treatments. RESULTS: In the laboratory nulliparous and parous mosquitoes preferred skin odours and combinations thereof over floral odours. However, in semi-field settings nulliparous were significantly more caught with floral odours, whereas no differences were observed for parous females. Combining floral and human volatiles did not augment attractiveness. CONCLUSIONS: Nulliparous and parous A. gambiae s.s. are attracted to combinations of odours derived from spatio-temporally segregated resources in mosquito life-history (floral and human volatiles). This is favourable as mosquito populations are comprised of individuals whose nutritional and developmental state steer them to diverging odours sources, baits that attract irrespective of mosquito status could enhance overall effectiveness and use in monitoring and control. However, combinations of floral and skin odours did not augment attraction in semi-field settings, in spite of the fact that these blends activate distinct sets of sensory neurons. Instead, mosquito preference appeared to be modulated by blood meal experience from floral to a more generic attraction to odour blends. Results are discussed both from an odour coding, as well as from an application perspective" |
| Keywords: | Animals Anopheles/*physiology *Chemotaxis Feeding Behavior Female Flowers/*chemistry Humans Odorants/*analysis Skin/*chemistry Tanzania Volatile Organic Compounds/*metabolism Anopheles gambiae Attraction Mosquito Skin Lure Vectrax Volatiles; |
| Notes: | "MedlineKemibala, Elison E Mafra-Neto, Agenor Saroli, Jesse Silva, Rodrigo Philbert, Anitha Ng'habi, Kija Foster, Woodbridge A Dekker, Teun Mboera, Leonard E G eng England 2020/09/03 Malar J. 2020 Sep 1; 19(1):318. doi: 10.1186/s12936-020-03395-2" |
