Bridging laboratory and field research: method adjustments to manipulate field-derived Aedes aegypti

Abstract

Reference strains of Aedes aegypti, reared over numerous generations under laboratory conditions, are selected to fit laboratory conditions and commonly used in research due to their consistency and ease of handling. However, working exclusively with such strains may not fully reflect the traits of natural populations. While working on such strains is relevant in terms of reproducibility between labs, it is also important to perform some work on field-collected mosquitoes and their progeny to capture more representative biological and behavioural variation. In this study, we used the New Orleans reference strain as a control to adjust and evaluate methods to manipulate the F1 progeny of field-collected mosquitoes from Cayenne (French Guiana). To improve blood feeding rate, we tested the impact of several blood feeding systems for mosquitoes kept in a cage or in individual vials and adjusted starvation time. To monitor fertilization, we assessed if dissection buffer affects burst of spermatheca during dissection, whether mosquitoes were collected alive of shortly after death. The results described here may be helpful for studies on mosquito fitness, particularly on field-derived mosquitoes or on experiments requiring individual level monitoring. Author summaryAedes aegypti is the major vector of dengue virus, causing hundreds of millions of cases per year. To fight against disease transmission, mosquitoes are studied in the laboratory, notably using colonies of mosquitoes kept over decades in the laboratory. These reference strains have been selected to fit laboratory conditions and may thus not fully reflect the traits of natural populations. While working on such strains is relevant in a sake of consistency between labs and ease of handling, it is also important to work on field-collected mosquitoes and their progeny to capture more representative biological and behavioural variation. In this study, we adjusted and evaluated methods to manipulate the F1 progeny of field-collected mosquitoes from Cayenne (French Guiana), using the New Orleans reference strain as a control. To improve blood feeding rate, we tested the impact of several blood feeding systems for mosquitoes kept in a cage or in individual vials and adjusted starvation time. To monitor fertilization, we assessed if dissection buffer affects burst of spermatheca during dissection, whether mosquitoes were collected alive of shortly after death. The results described here may be helpful for studies on mosquito fitness, particularly on field-derived mosquitoes or on experiments requiring individual level monitoring.