Hi, this is just my oppinion...
I agree the temp is not too high, I would not give Banamine or Bute, because it will mask the problem getting better or worse, and you wont know what your dealing with. A horse can have an "off day" and get through it with just careful monitoring and a vet call if he goes downhill, but if he is drugged you wont know if he is getting better or worse. It could be that the hay is bad, maybe just a flake or two had a bit more moisture in it and didnt dry out before developing a bit of mold. Open a new bale and try that hay. If a cat pees on hay my horses wont eat it, do you have cats ? Try not giving him grain, let him develope an appitite then try the hay from a new bale that the other horse will eat so you know the hay is good. My horses would prefer grain to hay also. How is the poop? dry? getting enough water? How is the pasture? any weeds he shouldnt be eating? when did you worm, did you worm the others too? feet hot? Laminitis? (too much grain is a killer for miniatures) These are all things you can examine without drugging your horse... In this country we use herbs to heal , banimine , bute , ace, even de wormers are all in the hands of vets , and even the vets wont use tany of these products unless its an emergency. How is his breath? does it smell like there is an infection? Hope it just a simple case of him having a few off days. Its really funny....ulcers almost never happen here, but we are also not alowed to self medicate, our tack stores sell tack , not medical supplies, not even iodine or wound salve. I had to learn how to deal with medical problems in a natural way, without self diagnosing...the vets get very angry when you
"play vet "here. It was hard to learn this new way of thinking , but the horses are just fine, with a simple gas colic once in a while, but even then the vets wont give Banamine, you take away hay, walk the horse or give them a big space to walk off the pain, horses dont feel pain like we do , they seldom need pain killers unless it is an emergency. European thinking is a bit extream in the other direction, but ya know, knock on wood, for us less is more. We dont believe in grain for our ponys either , even when building muscle , just a bit more hay and vitamins. Americans can be a bit extream , I know I use to be one of them.