Join Date: Jan 2012
Location: An English Girl living in beautiful Alberta, Canada
• Horses: 0
To the OP for allergy testing.
Horses are most likely to be allergic to things they have ingested, second things they have inhaled, third things they touch.
The allergy can be instant (like bee sting reaction), or it can build up over time as exposure increases.
If the allergy manifests as urticaria (spots or lumps in skin), this can cause itching that will cause scratching that can lead to secondary bacterial skin infection. So if your horse is itching it is a good idea to get a course of treatment of steroids. This will 1 - relieve the symptoms 2 - confirm it is an allergic reaction is (1) happened, and 3 - stop the secondary infection occurring.
After that, take your horse down to basics to eliminate and identify allergens. Cut hard feed down to nothing if possible, or to the US equivalent of a grass chaff and sugar-beet diet. If stabling, use only one type of bedding. If in pasture, choose one with only grass; no shrubs etc. Don't use feed supplements, don't bathe with any soaps or shampoos, don't wash your saddlecloths in laundry powder, etc etc.
Then... wait four weeks. If the allergic reaction is still there, start to eliminate things. Slowly.
In my own experience the allergen is obvious within 48 hours of exposure and clear as quickly, but the scientific advice is that it can take up to four weeks so I leave it with you to go on gut feel on this!
Blood Tests. Expensive and non-conclusive. Speak to your vet but I never found one authority on allergies that found them useful.
Vets. In My part of the world I quickly discovered that allergic reaction is such a comparitively rare problem that whilst I am not a scientist in any way, I have a bette understanding of how allergies work in horses than my vet did.
Finally, I mentioned Professor Knottenbelt of Liverpool University in the UK. He is South African, he travels the world lecturing on his specialist subject (skin problems in horses), and he helped me with my diagnosis for free over the e-mail and telephone. Look him up on google and when you are a bit further down the road, contact him. There's nothing to be lost by trying.
Oh, and it might just go away, they sometimes do :)
Get up, get going, seize the day. Enjoy the sunshine, the rain, cloudy days, snowstorms, and thunder. Getting on your horse is always worth the effort.