Testing can be very inconclusive. Most vets go with the treat and see if they improve. There are not any negatives to putting a horse on an IR diet.

And fyi my horse did not rub from the halter portion of the muzzle but the basket part. I tried to figure out ways to keep the sores down but was unsuccessful.

Riding a horse is not a gentle hobby, to be picked up and laid down like a game of solitaire. It is a grand passion. It seizes a person whole and once it has done so, he will have to accept that his life will be radically changed. Ralph Waldo Emerson

Tack for Sale! http://fhotd64476.yuku.com/topic/67755/Saddle-girth-pad-and-bridle