I never had my horse scoped, but I’m pretty sure he developed ulcers shortly after being moved from his home where he’d grown up and spent 10 years to a boarding barn. I was clueless about ulcers (having never dealt with them before) and didn’t have him scoped nor did I treat. I chased every other possibility for his behavior and various issues (tense back, dropping weight, etc) and eventually he improved but was never what I’d called “cured” of this “new normal” for him. I even moved him to a different barn and he improved even more (more hay, better overall set-up for him). Then we moved this last time to our new (and favorite) place, and he went absolutely nuts. I took advice from this forum to treat for ulcers and within a day of his first full tube of Ulcergard he was improving. By the end of 30 days, he was his old self from “back home” where he’d spent most of his life.
We’ve been at our new barn for a year and a half (I think) and he’s never relapsed. I truly believe he’d been dealing with the ulcers for a few years. They’d improve with management changes and such, but never went away and when we made that final move, the ulcers flared with a vengeance and he let me know it.
Now I make sure he eats tons of grass hay, some form of alfalfa (cubes, chopped, baled, pellets), about 6 Outlast cookies a day, and is in a situation with 24/7 access to a small pasture and a nice, comfy stall (with a fan) with his good buddy. He’s happy as a clam and it shows in both his calm demeanor and slick, shiny, dappled, plump physique. I’d forgotten just how easy of a keeper he used to be back when I had my place. He’s that again. (My barn is self-care so it helps that his “mama” is feeding him, hehehe).
All this to say, in my one experience, I do think they can IMPROVE, but I sort of think they’re always there if they’ve not been treated, and therefore any little thing may cause them to flare up again.