Validation of site-specific spraying of cattle for trypanosomosis control in areas infested with glossina fuscipes fuscipes in Uganda

Abstract

In a bid to enhance bovine trypanosomosis control in tsetse-infested rural areas in Uganda by livestock keepers, restricted application of deltamethrin to legs and ventral abdomen of cattle was assessed for its effectiveness in reducing the prevalence of trypanosomosis and tsetse apparent density in areas infested with Glossina fuscipes fuscipes over a 10-months period. The study was conducted in 9 villages in Amuria, Dokolo and Kaberamaido districts from December 2008 to September 2009. A total of 600 cattle were sprayed and tested for trypanosomosis every four weeks in six experimental (sprayed) villages, two per district. In addition, 300 cattle were tested for trypanosomosis every four weeks in three control (non-sprayed) villages, one per district. Simultaneously, tsetse-trapping was conducted to assess reduction in tsetse apparent density in both experimental and control villages. A decline in the prevalence of trypanosomosis from 10% to 0%, 12% to 1% and 11% to 0% was achieved in experimental villages in Amuria, Dokolo and Kaberamaido, respectively, between December 2008 and July 2009. Correspondingly in the same villages, a decline in the tsetse apparent density from 3.0 to 0.0, 2.7 to 0.0 and 1.5 to 0.0 was achieved in Amuria, Dokolo and Kaberamaido, respectively, between December 2008 and July 2009. In contrast in control villages, the prevalence of trypanosomosis in cattle varied from 7% to 12%, 3% to 18%, and 3% to 10% in Amuria, Dokolo and Kaberamaido, respectively, during the same period. In same villages, the apparent tsetse density varied from 0.8 to 1.2, 0.8 to 3.0, and 0.2 and 2.4 in Amuria, Dokolo and Kaberamaido, respectively, over the same period. This study revealed a 100% decline in prevalence of trypanosomosis over a period of 8 months; and a 100% decline of tsetse apparent density over a period of 7 months. Cattle in experimental (sprayed) villages had a significantly higher (P < 0.05) mean PCV than those in control (non-sprayed) villages. The low-cost property of this method associated with reduced amount of insecticide used; its simplicity of application and quick effect in improving the health of livestock; and its ability to simultaneously control tsetse and ticks, tremendously attracted farmers’ participation.

Keywords: Site-specific; spraying; cattle; trypanosomosis control; Glossinna f. fuscipes; Uganda