Effects of Ethidium® (homidium bromide) on female reproductive performance of laboratory-reared tsetse flies, Glossina morsitans morsitans Westwood (Diptera: Glossinidae)

Ethidium® (homidium bromide) is a trypanocide likely to be encountered as a violative residue in blood collected from abattoirs for feeding laboratory tsetse flies. We investigated its effect on female reproduction of Glossina morsitans morsitans. One-milligram homidium per kilogram body weight was intra-muscularly administered to four steers and blood aseptically collected from them between 15 and 30 min post-treatment, analysed for homidium levels and processed for tsetse feeding. Two hundred teneral female flies were fed on homidium-treated diet while a control group of similar number was given untreated diet and the reproductive performance of the two groups statistically compared. Ethidium®, at 266.15 ng homidium/ml blood diet, halved A-class portion of F1-pupae, highly reduced decline of F1-progeny quality associated with aging parents, but had no significant effect on the pupae viability, fecundity and abortion rate of the flies. We therefore concluded that Ethidium® has beneficial effect on laboratory tsetse attributable to clearance of unfavourable microbes mediated by the drug, and could be used as a tsetse diet additive.