Suitability of a chilled environmental box of the Precision X-RAD 320 cabinet style irradiator for the irradiation of mosquitoes and tsetse in the context of the sterile insect technique

A cabinet-style small animal X-irradiator outfitted with an environmental chamber which can provide a consistent, chilled environment during irradiation was tested to sterilize the human and animal disease vectors Aedes aegypti Linnaeus (Diptera: Culicidae), Anopheles arabiensis Patton (Diptera: Culicidae), Glossina palpalis gambiensis Vanderplank (Diptera: Glossinidae) in the frame of the sterile insect technique (SIT). The environmental chamber enables the irradiation of immobilized, compacted adult insects avoiding mechanical damage incurred by movement and, thereby, maintaining better insect quality. For the species tested, there was no significant difference in dose response when irradiating late-stage pupae or adults, and chilling at 7 °C did not affect irradiation outcome in terms of sterility induced. The X-irradiator was shown to be effective and suitable for the sterilization of these important target species of the SIT and offers a practical means to sterilize insects at the adult stage which require chilling for immobilization.