Pyrethroid Treatment of Cattle for Tsetse Control: Reducing Its Impact on Dung Fauna
PLoS Neglected Tropical Diseases
Natural Resources Institute, University of Greenwich, Chatham, United Kingdom; South African Centre for Epidemiological Modelling and Analysis, University of Stellenbosch, Stellenbosch, South Africa; Division of Tsetse Control, Harare, Zimbabwe; Liverpool School of Tropical Medicine, Liverpool, United Kingdom; Warwick Medical School, University of Warwick, Coventry, United Kingdom
African trypansomiases of humans and animals can be controlled by attacking the vectors, various species of tsetse fly. Treatment of cattle with pyrethroids to kill tsetse as they feed is the most cost-effective method. However, such treatments can contaminate cattle dung, thereby killing the fauna which disperse the dung and so play an important role in soil fertility. Hence there is a need to identify cost-effective methods of treating cattle with minimal impact on dung fauna. We used dung beetles to field bioassay the levels of dung contamination following the use of spray and pour-on formulations of deltamethrin, applied to various parts of the body of cattle in Zimbabwe. Results suggested that dung was contaminated by contact with insecticide on the body surface as the cattle defecated, and by ingestion of insecticide as the cattle licked themselves. Death of dung beetles was reduced to negligible levels by using only the spray and applying it to the legs and belly or legs alone, i.e., places where most tsetse feed. The restricted applications suitable for minimising the impact on dung fauna have the collateral benefits of improving the economy and convenience of cattle treatments for tsetse control. The demonstration of collateral benefits is one of the surest ways of promoting environmentally friendly procedures. © 2015 Vale et al.
deltamethrin; deltamethrin; insecticide; nitrile; pyrethroid; Article; bioassay; bullock; cattle farming; economic aspect; Glossinidae; insect control; leg; microbial contamination; mortality; nonhuman; stomach; animal; beetle; bovine; drug effects; feces; insect control; parasitology; procedures; Zimbabwe; Animals; Beetles; Cattle; Feces; Insect Control; Insecticides; Nitriles; Pyrethrins; Zimbabwe
R7539, DFID, Department for International Development; R7987, DFID, Department for International Development