Culexlarvae are well adapted to growing and developing in containers, and therefore collecting and rearing field-collectedCulexto adulthood in the laboratory is relatively straightforward. What is substantially more challenging is simulating natural conditions that encourageCulexadults to mate, blood feed, and reproduce in laboratory settings. In our experience, this is the most difficult hurdle to overcome when establishing new laboratory colonies. Here, we detail how to collectCulexeggs from the field and establish a colony in the laboratory. Successfully establishing a new colony ofCulexmosquitoes in the laboratory will allow researchers to evaluate physiologically, behaviorally, and ecologically relevant aspects of their biology and better understand and manage these important disease vectors.
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Points to Consider When Establishing and Rearing Culex Mosquitoes in the Laboratory
Culexmosquitoes transmit several pathogens to humans and animals, including viruses that cause West Nile fever and St. Louis encephalitis and filarial nematodes that cause canine heartworm and elephantiasis. Additionally, these mosquitoes have a cosmopolitan distribution and provide interesting models for understanding population genetics, overwintering dormancy, disease transmission, and other important and ecological questions. However, unlikeAedesmosquitoes that produce eggs that can be stored for weeks at a time, no obvious “stopping” point exists in the development ofCulexmosquitoes. Therefore, these mosquitoes require nearly continuous care and attention. Here, we describe some general considerations when rearing laboratory colonies ofCulexmosquitoes. We highlight different methods so that readers may choose what works best for their experimental needs and laboratory infrastructure. We hope that this information will enable additional scientists to conduct laboratory research on these important disease vectors.
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- Award ID(s):
- 1944324
- PAR ID:
- 10521083
- Publisher / Repository:
- Cold Spring Harbor Protocols
- Date Published:
- Journal Name:
- Cold Spring Harbor Protocols
- Volume:
- 2023
- Issue:
- 8
- ISSN:
- 1940-3402
- Page Range / eLocation ID:
- pdb.top107823
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Dormant propagules can provide a rapid colonization source for temporary aquatic habitats and set the trajectory for community dynamics, yet the egg banks of stormwater management systems have received little attention. We asked which species hatched from the sediment of drainage ditches in Champaign County, IL, and found bdelloid rotifers and ostracods (Heterocypris incongruens) to be the most common taxa. These sites also are colonized by mosquitoes, and we established laboratory experiments to examine interspecific interactions between common co‐occurring taxa.Culex restuanslarvae were reared in the presence or absence ofH. incongruensat two intra‐ and interspecific densities (20 or 40 total individuals) and their survivorship to adulthood, development time to adulthood, adult body size, and sex ratio were determined. Survival forCx. restuanswas significantly lower at high larval density than at low larval density in both treatments.Culex restuanslarvae reared in the presence ofH. incongruenshad a shorter development time to adulthood and emerged as larger adults compared to those reared in the absence ofH. incongruens. The sex ratios in theH. incongruenstreatments were female‐biased whereas those in theCulex‐only treatments were male‐biased. These differences may have epidemiological implications, as only female mosquitoes serve as disease vectors. Our results emphasize the importance of understanding interspecific interactions in influencing larval mosquito development traits.more » « less
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