Structural design affects entry response of mosquitoes in olfactometers

摘要

Host-seeking of the malaria mosquito Anopheles gamhiae sensu stricto is mediated by human odours. Dual-choice olfactometers are used to identify attractive odour components. We examined whether an olfactometer equipped with a funnel as trap entry would catch more mosquitoes than when with a baffle. When tested directly against each other using a human skin extract as stimulus, the funnel caught more mosquitoes in the first of the two experiments performed. In the second experiment, worn socks were used as an attractive odour source instead of human skin washings. This experiment showed that the total response of mosquitoes was significantly higher when funnels were used in both trapping devices than when baffles were used. Increasing the total number of mosquitoes trapped by using a funnel, can make it easier to distinguish which odour is more attractive when odours are tested that only differ little in their attractiveness.