Abstract
To achieve consistent and standardized rearing for mosquito immature stages, it is crucial to control the initial number of larvae present in each larval tray. In addition, maintaining an optimal and synchronized development rate of larvae is essential to maximize the pupal production and optimize male sorting in a mass-rearing setting. Manual counting is labor intensive, time consuming and error prone. Therefore, this study aimed to investigate the use of a customized automated counter for the quantification of mosquito larvae. The present prototype of the mosquito larval counter uses a single counting channel consisting of three parts: a larvae dispenser, an electronic counting unit and computer control software. After the separation of the larvae from eggs and debris, batches of different numbers of Aedes aegypti first instar larvae were manually counted and introduced into the counter through the upper loading funnel and channeled out from the bottom of the counter by gravitational flow. The accuracy and repeatability of the mosquito larval counter were determined in relation to larval density and water quality. We also investigated its impact on larval survival. Results showed an impact of larval density and water quality on the accuracy of the device. A −6% error and a repeatability of +/− 2.56% average value were achieved with larval densities up to 10 larvae/mL of clean water. Moreover, the use of the mosquito larval counter did not have any effect on larval survival or development. Under recommended conditions, the mosquito larval counter can be used to enumerate the number of mosquito larvae at a given density. However, future developments involving the use of multiple channels or larger input larvae container would help to expand its use in large-scale facilities.
Highlights
Mosquitoes are insects broadly distributed around the world, in tropical and sub-tropical regions
The mosquito larval counter (MLC) single channel (CH1) model is an automated system designed and developed in collaboration with Radiation General Ltd (RadGen), Budapest, Hungary to count immature stages of the mosquitoes, including L1s, as they pass through the optical sensor unit
The negative number indicates that the MLC underestimated the number of larvae by 7.14% of its reference or manual count value
Summary
Mosquitoes are insects broadly distributed around the world, in tropical and sub-tropical regions. The initial number of larvae present in each rearing tray should be controlled to accurately measure or estimate the effect of any factor on mosquito development or life history traits. The purpose of this study was to investigate the efficacy of the MLC-CH1 v1.0 to perform automated counting of first instar mosquito larvae with the ultimate goal of controlling the initial larval rearing density and standardizing the overall rearing process. The objectives were to: (i) determine how closely a measure from the MLC-CH1v1.0 approximates its true value (reference to manual counting) (hereafter referred as accuracy); (ii) determine the closeness of multiple measurement values (repeatability), (iii) evaluate the effect of larval density on the accuracy, (iv) evaluate the possibility of using the MLC for other mosquito stages and species and (v) examine whether MLC treatment negatively affects survival and development of MLC counted larvae
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
