Colonisation and mass rearing: learning from others

Abstract

Mosquitoes, just as other insects produced for the sterile insect technique (SIT), are subjected to several unnatural processes including laboratory colonisation and large-scale factory production. After these processes, sterile male mosquitoes must perform the natural task of locating and mating with wild females. Therefore, the colonisation and production processes must preserve characters necessary for these functions. Fortunately, in contrast to natural selection which favours a suite of characteristics that improve overall fitness, colonisation and production practices for SIT strive to maximize only the few qualities that are necessary to effectively control populations.However, there is considerable uncertainty about some of the appropriate characteristics due to the lack of data. Development of biological products for other applications suggest that it is possible to identify and modify competitiveness characteristics in order to produce competitive mass produced sterile mosquitoes. This goal has been pursued -and sometimes achieved -by mosquito colonisation, production, and studies that have linked these characteristics to field performance. Parallels are drawn to studies in other insect SIT programmes and aquaculture which serve as vital technical reference points for mass-production of mosquitoes, most of whose development occurs -and characteristics of which are determined -in an aquatic environment. Poorly understood areas that require further study are numerous: diet, mass handling and genetic and physiological factors that influence mating competitiveness. Compromises in such traits due to demands to increase numbers or reduce costs, should be carefully considered in light of the desired field performance.

Pre-copula acoustic behaviour of males in the malarial mosquitoes Anopheles coluzzii and Anopheles gambiae s.s. does not contribute to reproductive isolation

“…However, Dao et al (2008) showed that when both species congregate inside huts, cross-species mating is as frequent as within-species mating, indicating that assortative mating breaks down when mating occurs indoors. This is consistent with reports observing the absence of assortative mating in lab-reared Anopheles colonies (Benedict et al, 2009;Paton et al, 2013), which, overall, suggests that chemical cues such as pheromones and cuticular hydrocarbons (Dao et al, 2008) and flight tones (Dao et al, 2008;Tripet et al, 2004) do not play a major role in species recognition. Data are given as the range and/or mean±s.e.m.…”

Mass Production of Genetically Modified <em>Aedes aegypti</em> for Field Releases in Brazil

“…aegypti (and other mosquito species) there is a significant size difference between the male and female pupae which can be exploited for sex separation techniques. The sorted RIDL males are then released in a control program as either pupae or as adults 11,12 .…”

Male mosquitoes as vehicles for insecticide

“…albopictus ADAM approach will require large-scale production, i.e., 'mass rearing,' of mosquitoes for release. This type of mass rearing operation is developed already and in use with other autocidal approaches, including Sterile Insect Technique (SIT) [47][48][49]. Furthermore, the potential benefit of PPF treatment to 'boosting' autocidal approaches has been highlighted previously [50].…”