The control of Glossina pallidipes, G. fuscipes fuscipes and G. morsitans submorsitans in southwest Ethiopia using a cypermethrin "pour-on" insecticide

Tsetse populations and trypanosome prevalence in cattle were monitored from 1986 to 1993 in the Ghibe valley, southwest Ethiopia. From January 1991 to October 1993 between 2000 and 4000 cattle were treated at monthly intervals with a synthetic pyrethroid insecticide, cypermethrine high-cis. A dosage of 1 ml per 10 kg bodyweight was used to control tsetse flies (Glossina spp.). Treatments were given as a 'pour-on' applications along the backlines of animals, using automatic drench-gun applicators. This resulted in a decline of 93 percent in the apparent density of G. pallidipes and of 83 percent in the apparent density of G. mortsitans submorsitans by 1993. This reduction was associated with a reduction in trypanosome prevalence in cattle of 74 percent, despite a high level of resistance to all available trypanocidal drugs. The numbers of Stomaxys spp. and Tabanidae were also significantly reduced (P<0.01).