Culicoides Midges Case Study

Treatment and Control Measures : The most vital control measure is the protection of animals from the contact with Culicoides midges. The recommended measures to avoid diseases associated with Culicoides midges include the vaccination, stabling at night, meshing of the stables, and the application of insect repellents both to animal and its stable environment. Around livestock Culicoides midges can occur in the remarkable high numbers especially on warmer nights and during times of excessive rainfall. At such times more than 1 000 000 blood seeking C. imicola females can be seizured in a single light-trap and if estimate is correct that this may represent less than 1% of number of midges active on a specific night, obviously illustrates the intensity of attacks that must on occasion be endured nightly
Sprays can be used weekly while in the cattle insecticide impregnated eartags may be effective for 4-6weeks, or even as long as 10 weeks against Culicoides midges (Wittmann, E.J. 2000). In Australia it has been found that, after Hereford cattle had been given a single subcutaneous the injection of Ivermectin at dose of 200 mcg/kg, mean mortality of the engorged Culicoides females 48 hours after feeding was 99% for 10 days after the treatment. An adversative effect is impact of Ivermectin on dung beetle fauna so imperative for sanitation. Study in North America reported very limited success against C. sonorensis following the application of 5% permethrin or 27% pirimiphos-methyl to dorsum of calves. Engorged Culicoides females that showed sublethal intoxication, recovered and afterwards produced matured batches of eggs of normal size. Conversely, a belly spray of 0,2% permethrin substantially decreased numbers of engorged females, and lowered the engorgement levels 3 and 7 days post- treatment, but by day 10 little effect was