Use of traps and screens impregnated with insecticide for animal trypanosomiasis control

Abstract

The traps and screens impregnated with remaining insecticide have been used around the Center of Research and Breeding of Avetonou (Togo) for animal trypanosomiasis control. For the experiments, two herds of indigenous trypanotolerant cattle have been chosen; they were both situated close to the riverine vegetation of Sio River infested with Glossina palpalis and Glossina tachinoides. The control herd lives in the area without any treatment while the close neighborhood of the experimental herd is treated with traps and screens impregnated with deltamethrin: 22 Challier bi-conical traps along 2.2 riverine vegetation km and 16 blue screens along 32 pasture hectares planted with selected mango-trees and orange-trees. Control surveys (entomological and protozoological) have been done every month; the animals recognized as infected with trypanosoma are treated with diminazene aceturate (3.5 mg/kg) whatever herd they belong. From December 1985 to December 1986, preliminary results obtained have been very encouraging: in the treated zone, there were not only a decline of glossina density (per trap per day) from 4.6 at the beginning of the experiment to 0.1 at the end, but also an important decrease of trypanosoma infection rate in animals, from 13.6 p. 100 to 1.66 p 100. Cattle productivity has been clearly improved (decrease of abortions and cases of calf mortality, increase of calving rate, etc.). However there was no change in control herd; trypanosomiasis rate went from 10 p. 100 to 10.4 p. 100. These preliminary results are very positive and show the benefit of the use of these traps and screens impregnated with insecticide.