Weird breathing? curiouss..?

My experience with my horse certainly was not caused by allergies. He had COPD. Please tell the owner about this and have him checked by a vet. Any umption by anybody on a horses health condition needs confirmation by a vet that knows what he is doing. I would be hard put to blame all of his breathing problems on allergies. If riding him makes his breathing worse, please don't ride him again until the vet gives the word that it is ok to ride him. It sounds like the hard riding may be causing him a lot of stress. Please tell the owner to have the vet check him.