The Culicoides are Coming!

It doesn't take a clairvoyant to know what a warm, wet winter means for the bug population around here in spring & summer.  One particular tiny but annoying bugger is the culicoides midge or “no-see-ums” whose bite packs an itchy punch, especially for horses that are reactive to it’s saliva.  This tiny gnat is associated with muddy, moist habitats which we have in abundance right now acting as a nursery for the upcoming assault.  You may not see ‘em but you’ll know they’re here by your irritated, itchy horse.

Culicoides tend to feed on either the dorsal (mane, tail) or ventral (belly) areas of the host animal, depending on the species of biting gnat. They fly only in the warm months of the year and are most active at dawn and dusk (crepuscular).  Horses often become allergic to the bites, scratching and rubbing, causing alopecia, excoriations, and thickening of the skin.  This allergic response is known as; Summer itch, Sweet Itch, Queensland Itch, IBH - Insect Bite Hypersensitivity and SSRD or Summer Seasonal Recurrent Dermatitis.

So what to do?  It’s important to be pro active since allergic reactions tend to get worse as each season progresses and the itching can be very difficult to control until the flies die off in the winter.  Self mutilation from itching with crusty, damaged skin can attract more flies creating a continuous cycle of irritation that can really get out of hand.  The best treatment is to minimize exposure.  Culicoides are weak flyers so electric fans in stalls are effective deterrents.  Fly sheets and masks are somewhat helpful but leave some areas exposed.  Fly repellants like “Swat” (Farnam) or “Belly Balm” (Jeffers) applied to affected areas are helpful when used early and frequently.  Fly products with a relatively high concentrations of pyrethroid-permethrin have the greatest effect on gnats.  We have also had success with a product called “Eco Vet”.  Because the flies are crepuscular (active early AM & around dusk) do not turn animals out during those times.  Environmental management is also important to decrease breeding areas in standing water and moist manure.  If you know your animal has seasonal fly allergies make a management plan right now for an itch free summer!