Abstract
Glossina morsitans, G. pallidipes and G. fuscipes fuscipes were fed on cattle or pigs that had been dipped in 0·00375% deltamethrin in water, 0–31 days previously. The knock down and survival of the tsetse were then followed in the laboratory. Although mortality was generally less the longer after the dip the flies were fed, all those that fed on the animals within 7 days of the dipping were killed and all those that fed within 21 days were at least knocked down. Glossina morsitans was slightly more susceptible than the other two species tested.