Horse’s skin, much like human skin, is not invulnerable to damage, disease or allergies in spite of its protective properties. Warmer weather can be particularly problematic particularly in terms of allergies and fly nuisance. Sweet Itch is a common issue for horses and the incessant itching it causes can lead horses to self-harm.
Biting midge is the main cause of sweet itch – some horses develop hypersensitivity to the saliva the midge releases when they bite. Generally speaking horses are genetically predisposed to this condition, with Shire Horses, Shetland Ponies, Welsh Ponies, Icelandic Ponies, Connemaras, Arabs, Warmbloods and Friesians as well as Quarter Horses being recognised as being at risk of this condition. It is for this reason that you may see certain horses even within the same locality unaffected by sweet itch, while others suffer badly from the condition.
Horses suffering from this hypersensitivity will suffer from a persistent itching – driving them to rub, bite and scratch to relieve this. A single exposure may cause itching for up to three weeks so preventing the bite is essential. As such the use of a suitable insecticide should begin before the fly season has begun and continue at regular intervals throughout the season. An insecticide, when properly applied, aims to kill the insect as quickly as possible after contact – no biting is needed, thus preventing the allergic reaction to the bite.
Signs of Sweet Itch include; chronic itching, hair loss and bald patches caused by rubbing (particularly on the base of the tail and the mane), open or bleeding sores, crusty or broken skin. Most signs are secondary traumas resulting from the need to alleviate the chronic itching caused by the allergic reaction. It is vital to consult with your veterinary surgeon to rule out any other conditions which many have similar signs and ensure a correct diagnosis.
Strategies for controlling sweet itch vary and cover a range of products/actions. As midges are generally more prevalent at dawn and dusk, simply keeping your horse stabled at these times will help. Use a close fitting fly rug which covers the neck, belly and base of the tail to prevent the midges access to the skin. A horse face mask may also be useful for the same reasons. A good fly repellent or insecticide to reduce midge challenge can also be used. Susceptible horses should be kept away from wet ground where midges proliferate. Insecticidal Shampoo for horses or lotions can help relieve irritated areas and cold hosing or the application of cold packs for horses can also bring temporary relief.