Feeding behaviour, survival and reproductive performance of glossina palpalis gambiensis infected with trypanosome (puttonella) vivax

Abstract

A study was carried out to determine the effect of Trypanoso a (Duttonella) vivax Ziemann infection in Glossina palpalis gambiensis Vanderplank on the survival and reproductive performance. feeding behaviour, A colony of this subspecies was maintained in the laboratory: results showed that the performance of the flies in terms of female survival and fecundity and weight of puparia produced was consistently good stock Teneral male and female flies infected with T. vivax ILRAD 3145 were compared with untnfected controls by measuring the following parameters: {l} mean number of feeds in 20 consecutive days; (2) mean rate of bloodmeal intake ug/sec. of the total days fed; (3)mean wei~hL of bloodmeal intake/day of the total days fed; (4)mean total bloodmeal engorgement in 20 days; (5)mean number of probes/day of the days fed; (6) mean frequency of the multiple probe feeds. (7 ) mean number of pre-feeding probes of the multiple and probe feeds. There were no significant differences 1 feeding between the infected and the uninfected controls. The results suggested that the presence of T. Vivax epimastigotes in the labrum had no deleterious effect on the feeding behaviour of the tsetse vectors. The frequency of probing during feeding by hungry tsetse flies in relation to transmission of T. vivax was also studied. The infected tsetse flies were 80J allowed to probe consecutively without feedin~ on two gats and then allowed to complete feeding on a third one, and the rate of transmission calculated. Evidence was found to suggest that infected flies transmitted trypanosomes both during probing and when they completed feeding on the susceptible hosts. The survival and reproductive performance of the infected and the uninfected flies were compared by recording daily mortality and pupal production of a group of 100 infected females and 88 infected males and an equal number of uninfected controls. Results suggested that the presence of trypanosomes in the mouthpart had no adverse effect on the survival of the flies. The weights of pupae produced were also not affected. suggesting that reproductive physiology of the female and the nutrition of the pregnant females in relation to nourishment of the intra- uterine larvae was not affected by infection of the flies with T. vivax.