Kate Hore RNutr(Animal). Snr Nutritionist at NAF
Sweet Itch is anything but sweet, and is the result of hypersensitivity to the saliva of the culicoides midge. After being bitten by the midge, the body launches a type 1 hypersensitivity reaction from the immune system, which results in histamine production. It is the histamine response which results in the itching and raised lumps of sweet itch.
Obviously these lumps are very itchy, hence why the horse will attempt to rub themselves repeatedly, on fences or even biting themselves, causing hair loss which opens the risk of a secondary bacterial in the skin itself.
There are a number of ways in which the risk of sweet itch can be reduced, though sensitive individuals will remain susceptible. Ultimately ensuring there is a physical barrier between the animal and the midges is a highly effective way to prevent exposure to the midge saliva. Skin tight, lycra style, rugs which cover the body, under the abdomen and the neck have proven to be a popular method to reduce exposure. If possible moving the horse away from wooded areas close to water is ideal, though unfortunately not always practical, as these kinds of environments are where midges thrive. Midges do tend to be more active at either end of the day, so stabling at dawn and dusk can again reduce exposure.