Anaesthetising Drosophila for behavioural studies.

The detrimental effect of anaesthesia by chilling or CO(2) on the mating behaviour of Drosophila melanogaster was investigated. Both agents significantly increased copulation latency, even when flies were given 20 h to recover from anaesthesia. CO(2) anaesthesia increased copulation latency more than anaesthesia by chilling. Delivery of a mechanical shock to the flies immediately before testing also increased copulation latency. These experiments demonstrate the sensitivity of insect behaviour to disruption by anaesthesia or rough handling. It is preferable to avoid anaesthetising flies that are to be used in behavioural studies.