My 9-year-old Missouri Fox Trotter gelding has steadily put on weight throughout his life, even though he is exercised two to three times a week on the trail at working gaits. He is free-fed Bermuda grass hay (not coastal) and no supplements, but he has developed a crest and fatty deposits on his body. My veterinarian tested his thyroid levels, and they were on the high side of normal. She has had him on thyroid powder for the last eight months and his weight has held steady. The tests for insulin resistance and Cushing’s disease are expensive–can I treat him and see if that helps? I am unable to cut back on his feed because he starts showing signs of ulcers. Do you have any suggestions?