I have a young Rocky that is the very definition of Air Fern. He's only 3.5 years old. In April, he was of a good weight... I had to go help a friend for a couple of weeks, and upon my return he had gained 100# (!!) In TWO WEEKS!
I've spent all summer and now this fall trying to get the weight off. He's been on pasture 24/7 but we recently moved to a new place where I have access to a stall. He isn't very happy about that, so the stall isn't yet seeing much use. I also noticed he sometimes stocks up a bit behind if left in a stall.
He gets no concentrates. He was at first wearing a grazing muzzle 12 hours a day, but for the last three months it's been on 24/7, except when he's been in the stall. In the stall, he has a small hole haynet with no more than three flakes of hay for a night.
He's down from fat to almost right (according to the vet), but I can't get that last 40# or so off of him! He hasn't lost any more weight in about the last month. He's too young to work hard enough to lose weight that way.
He gets some forage balancer cubes (about two cups, soaked to double the volume) with a Smartpak vitamin/mineral supplement, once a day, in addition to graze (with muzzle) or haynet.
Could he have a metabolic condition at such a young age? I've tried hard to keep him from getting fat, but at least one of the feeders at my original place had other ideas, which was one reason I moved (The BO honored my feed requirements, but I found prepared feed that was over twice that, on the weekends where the help feeds). That was in June.
Probably unrelated, but despite being in great health (aside from the weight), including some dappling, he has gained no height since last spring! He's been 14.2hh for a very long time, and this seems strange to me. He has "remodeled", gaining some chest and butt (not-fat width) and putting on some muscle (he was in a hilly pasture for a while - got fitter but not really much thinner).
Any help is appreciated. Have you come across a problem like this before?