Dr. Eleanor Kellon, Staff Veterinary Specialist for Uckele Health & Nutrition
Sweet itch is the common name used to describe an allergic reaction to the bite of the midge Culicoides. These tiny terrors don't look any more threatening than fruit flies but for horses allergic to the saliva in their bites they start an agonizing cycle of itching, rubbing, hair loss and skin breakdown.
The primary area affected is the tail base and hindquarters. They may also rub their mane. If mane rubbing is seen, especially without hindquarter involvement, be sure to also check for ticks. Some horses also rub and break down along their lower belly. This area can be irritated, as well, by migrating larvae of the neck threadworm, Onchocerca.