Observations on the effects of antibiotics in the blood meal of Glossina species

Abstract

Reduced productivity of two self-producing colonies of Glossina palpalis palpalis and G. tachinoides maintained in vivo on rabbits whose diets contained oxytetracycline and salinomycin antibiotics, was observed. Fecundity of both of the species declined, but not their survival rates. Examination of their reproductive systems revealed a high proportion of G. p. palpalis females in a less advanced reproductive cycle with few abnormalities, while G. tachinoides females showed a deep degeneration of developing follicles. A considerable reduction in the number of mycetocytes of G. tachinoides was observed, while G. p. palpalis was only slightly damaged. Use of animal hosts on additive-free diets resulted in an improved productivity of G. p. palpalis, but not G. tachinoides. It is recommended that the use of additives in the diet of animals used for feeding tsetse colonies must be avoided. The attempt to use a locally formulated diet based on soyabeans and zea mays supplemented with vitamin C gave excellent results.