Sweet Itch
Taken from advice issued by the Great Britain Pony Clubs UK
Sweet Itch is a problem that affects thousands of horses, ponies and donkeys in many countries to a greater or lesser degree. Virtually all breeds and types of ponies and horses can be affected, from Shetlands to draught horses, although it is rare in English Thoroughbreds.
Symptoms
include severe itching, hair loss, skin thickening and flaky dandruff. Weeping sores, sometimes with a yellow crust of dried serum may occur. Without attention sores can suffer secondary infection.
The top of the tail and the mane are most commonly affected. The neck, withers, hips, ears and forehead, and in more severe cases, the mid line of the belly, the saddle area, the sides of the head, the sheath or udder and the legs may also suffer.
The animal may swish its tail, roll repeatedly and attempt to scratch on anything within reach. Scratch out their mane with their hind feet and bite at their own tail, flanks and heels .
They may drag themselves along the ground to scratch their belly or sit like a dog and propel themselves round to scratch the top of their tail on the ground.
It may pace continuously and seek mutual grooming from field companions.
There can be a marked change in temperament the horse may become irritated when ridden. When flying insects are around he may become restless with repeated head shaking.
Horses that develop Sweet Itch usually show signs of the disease between the age of one and five and it is common for the symptoms to appear first in the autumn.
Sweet Itch is probably hereditary however environmental factors play a major part where the horse is born and where it lives as an adult are at least as significant as the bloodlines of its sire and dam.
Sweet Itch is not contagious, although if conditions are particularly favorable to a high midge population, more than one horse in the field may show symptoms.
In the United Kingdom Sweet Itch is classified as an unsoundness and,
as such, should be declared when a horse is sold.
Causes Sweet Itch is an allergic reaction and therefore an immune system problem.
The disease is a delayed hypersensitivity to insect bites and results from an over enthusiastic response by the animal's immune system.
In the process of repelling invading insect saliva ( which actually contains harmless protein ) the horse attacks some of its own skin cells , and resulting cell damage causes the symptoms described as Sweet Itch.
At present there is no cure for Sweet Itch. Once an animal develops the allergy it generally faces a distressing period every spring, summer and autumn.
Treatment
Avoid marshy, boggy fields.
If possible move the horse to a more exposed windy site, bare hillside or a coastal site with strong onshore breezes.
Chalk based grassland will have fewer midges than heavy clay pasture.
Ensure pasture is well drained and away from rotting vegetation such as muck heaps, old hay feeding areas, rotting leaves
.
Stable at dusk and dawn, when midge feeding is at its peak, and close stable doors and windows ( midges can enter stables ).
Use a fly repellent.
Benzyl benzoate was originally used to treat itch mites ( scabies ) in humans and has been used for many years to combat Sweet Itch.
In its neat form it is a transparent liquid with an aromatic smell, but it is more commonly obtained from Vets or pharmacies as a diluted milky white suspension. It should be thoroughly worked into the skin in the susceptible areas every day.
It is a skin irritant and should not be used on the horse if hair loss and broken skin have occurred application should therefore start before symptoms develop in the spring.
Gloves should be worn when applying insecticides, including benzyl benzoate. Particular care should be taken if they are used on ponies handled by children they can cause eye irritation, for example if fingers transfer the chemical from the pony's mane to the eyes. |
