Effects of permethrin (Flypor®) and fenvalerate (Acadrex®60, Arkofly®) on Culicoides species - the vector of Bluetongue virus.

Bluetongue disease struggles ruminants in Europe since summer 2006, introducing high levels of morbidity and mortality. Besides vaccination, the application of insecticides is another means to protect cattle and sheep from infections with the Bluetongue virus, which is transmitted in Europe by female specimens of Culicoides species (Culicoides obsoletus and in a few cases of Culicoides pulicaris and Culicoides dewulfi). The present study deals with the effects of permethrin (Flypor®) and fenvalerate (Arkofly®, Acadrex® 60) on freshly caught Culicoides specimens when brought into contact for 15, 30, 60 or 120 s with hair of cattle or sheep treated topically 7,14, 21, 28 or 35 days before. The experiments clearly showed that the lege arte application of these compounds (products) onto the hair of the experimental animals succeeds in killing Culicoides specimens when brought into contact with hair from feet of animals being treated even 35 days before. This test was needed to make sure that the products do reach the feet and belly of the animals in sufficient amounts, since this region is the predominant biting site of the Culicoides midges.