It’s that time of year again that many horse owners dread – sweet itch season! Sweet itch affects lots of horses causing itching of the skin and in some cases significant pain and discomfort.
Sweet itch is the term used to describe the skin condition in horses that are allergic to the bite from the common midge also known as Culicoides. Due to the direct involvement of the midge, the problem is seasonal as they are mainly seen during spring, summer and autumn. Midges tend to come out at dusk and dawn and tend to be located near water and trees as they like damp, humid conditions.
What are the signs of sweet itch?
The main symptoms displayed by affected horses are itching mainly around the mane and tail but can be itchy anywhere on their body. In mildly affected horses, this can be seen as broken hairs on their mane and tail, and bald patches on the body from scratching. More severely affected horses can be so itchy that they can break the skin and cause wounds which require veterinary treatment. Some horses have also been known to break fences from scratching some vigorously.
How do I help manage sweet itch in my horse?
Management of sweet itch is complex as some of those horses allergic to midge bites are also allergic to other environmental allergens. As vets we would always advise a thorough investigation of allergic skin disease to achieve as accurate a diagnosis as possible.
Options available for helping manage sweet itch are:
- Housing your horse at dusk and dawn i.e. usually from 4pm – 8am, when the midge is most active. You can also place fans in the stables at this time to provide a strong ‘breeze’ in your horse’s stable
- Avoid grazing your horse near water or trees, and graze in more exposed fields with a good breeze – midges get blown away in winds over 4mph!
- Rugs that help prevent access to your horse’s skin such as Boett rugs can be helpful
- Topical treatments such as Z-itch, Switch or Deosect which can help repel flies and midges.
- Barrier treatments such as Avon skin-so-soft or benzyl benzoate are also useful.
- Soothing shampoos containing oatmeal , aloe vera and borage can help calm irritated skin
- There is limited research available and also anecdotal evidence from owners of horses suffering from sweet itch suggests feed supplements designed to support skin health can help. This included things like Cavelesse, Brewer’s Yeast or vitamin B supplement
- In more severe cases, your vet may have to prescribe short courses of steroids to try to break the itch scratch cycle. There is also a vaccine available which can significantly improve management in some cases. Speak to your vet about these treatments.
Management of these cases can be challenging at times and it is best to be as proactive as possible prior to the fly season
Dr Nicola Endersby MRCVS
