Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/17/2011
Publication Date: 5/2/2011
Citation: Clark, G.G., Bernier, U.R., Allan, S.A., Kline, D.L., Golden, F.V. 2011. Changes in host-seeking behavior of Puerto Rican Aedes aegypti (L.) after colonization. Journal of Medical Entomology. 48(3):533-537. doi: 10.1603/me10207.
Interpretive Summary: In the past, concerns have been expressed over the innate behavioral differences of mosquitoes maintained for a long duration in a colony versus mosquitoes recently introduced from the field. Colonization of mosquitoes usually requires some adaptation of the adult mosquito feeding behaviors (to obtain sugar meals for energy and blood meals for reproduction by females), mating behaviors and oviposition behaviors while under confined laboratory conditions. Naturally, this will impart a selection bias towards those that can adapt more rapidly to rearing under colony conditions. The subsequent changes in behavior associated with this adaptation may influence the outcome of laboratory-based bioassays that involve examination of host-seeking behavior, repellents, and insecticides. The objective of this study was to define and compare attraction responses to host odors between succeeding generations of a newly established strain of Aedes aegypti from Puerto Rico with a laboratory strain that had been colonized for over 50 years. The outcome of this study should enhance the interpretation, comparison and correlation of laboratory responses to allelochemicals, and particularly kairomones in the case of this study, for newly colonized mosquitoes compared to those maintained in colony for an extended period of time.
Technical Abstract: The effects of colonization on host-seeking behavior of mosquitoes was examined by comparing attraction responses of newly colonized Aedes aegypti (L.) from field-collected eggs in Puerto Rico to that of the Gainesville (Florida) strain, originally from Orlando (Florida) and in colony since 1952. Females from the Orlando and the F0 through F10 generations of the Puerto Rico strain were evaluated by staff at the USDA’s Center for Medical, Agricultural and Veterinary Entomology (CMAVE) in Gainesville, Florida using attractant odors in a triple-cage dual-port olfactometer. Two attractant sources were used: odors from the hand of a volunteer and a standard blend of L-lactic acid, acetone, and dimethyl disulfide. Convergence of the percentage of attraction responses occurred around the F4-F6 generations of the Puerto Rico strain. Both the Orlando and Puerto Rico strains exhibited similar responses for tests with the remaining F7-F10 generations. A temporal effect on mosquito responses was observed for both strains regardless of the attractant blend used in tests. This study indicates that Ae. aegypti host-seeking behavior changes significantly over the first 4-6 generations after introduction into the laboratory, where the field-collected strain increases in attraction response until it stabilizes at a new level.