Residual effects of benzyl benzoate parasiticide tested on Glossina p.palpalis Robineau Desvoidy (Diptera : Glossinidae)

Abstract

The effects of benzyl benzoate (BP) parasiticide were evaluated in the laboratory on the survival and reproductive performance of Glossina p. palpalis using rabbits as feeding host in order to determine the safety margin post drug application, None of the flies fed on animals offered 30 min (i.e. group A) post drug application took any meal during two days. The survival of the batch was poor in that 40.0 % died by day +35 with a total puparia production of 12. Except for a slight (p > 0.05) improvement in their feeding response and fecundity, the performance of batch of flies fed on animals 2 and 5 days (groups B and C) post drug application is poor, similar to that recorded for group A. The survival and productivity of flies fed 7 days (group D) post drug application were good, but those of flies fed 14 days (group E) post drug application were better and not different (p > 0.05) from the control group. The quality of puparia produced by flies fed on groups A-C animals was low, with a mean of 19.6 ± 1.1 mg compared to 26.8 ± 1.4 mg and 28.1 ± 0.9 mg for flies fed on groups D and E, respectively. The results indicate a gradual improvement in both feeding response and productivity with time post drug application. Minimum duration considered safe for feeding tsetse flies on benzyl benzoate treated animals without fear of residual effects is 3 weeks.