Just like humans, horses age in different ways. If he’s always been honest and nothing has changed in your training program etc I’d have a vet go over him closely. A friend had her 100% honest horse suddenly stop at the base of an oxer, she fell on the back rail and was hurt (not seriously.) Trainer got on and felt no “lameness” but clearly something was wrong. The horse given a full workup and they discovered that a titre showed he was riddled with Lyme Disease. Vet had never heard of a number so high!
Once he was treated he was fine and didn’t stop again.
Honest horses don’t just start to stop unless something is bothering them. Don’t forget his front legs/feet. The landing mechanism takes pounding and if they are worried about it hurting to land, they hesitate to take off.
IMHO mileage has NOTHING to do with it and neither does age. I have had horses retire from jumping all together at 13 years old due to injury and others jump 3’ into their 20’s. Some of us break down sooner than others.
If your horses is stopping I would probably get the vet to do a check, possibly some xrays just to see where your horse is at and if you need to begin management of some kind.
We have an amazing Arabian who at 29, is still loving jumping, of course on joint meds, and not nearly as often
Very old thread. Maybe start a new one?
SUPER zombie thread. Is this an april fools thing? There have been a ton today.
We just had a little schooling show. Ex hunter Hony (overgrown pony) cleaned up in the 3’ jumper division at age 25! Sound, happy, much less mischievous than he was in his youth … and almost no maintenance. No reason to stop!
Well if the original Op hasn’t fired out by now, that she should have consulted her veterinarian, it’s a little late for me to tell her that.
But, IMHO a sudden change in a horse’s ability needs to be investigated before accepting a trainers.“HoHum”.
I am a firm believer that horses “misbehave” because they are in pain. I second most comments in that you should have him checked out by a vet.
I also recommend considering true “breaks” for the horse. Maybe a month off in the winter of NO riding. This has REALLY helped my older guy.
Theres’ really no age limit. My mom has a 24y/o Oldenburg gelding that still trucks around training level eventing. We also used to own a 20y/o OTTB who did 3’ hunters until he was 25.
Short answer, soundness.
I know this thread is ancient, but I’ll take any opportunity to gush about this guy. The horse I lease turns 26 next month and is still going strong. We competed in the 2’3" last year/the year before and won just about everything. He’s been well maintained his entire career, and is a hearty little TB with great bone. He’ll probably start ramping down this year, but only because there’s no need to overdo it — and he’s more than earned it!
Horses like this are a true treasure. I know a few who just keep trucking at the lower levels with basic maintenance. I hope my horse will (in a very long while) be one of those horses.
Your boy is adorable!
Ooo, the rarely seen double zombie thread! Lol.
I will agree that it totally depends on the individual horse. There are horses that don’t want to jump any more when they are six years old, and there have been horses still winning the Grand Prix classes at the age of 20. Flexible comes to mind, for one.
Teehee. 
It is!!
My last three oldsters…one jumped 3’ reliably till he was about 23. He never felt off or never refused a fence, but I felt it was kinder to let him retire from jumping. My next one started feeling funny and not “right” jumping at about 20. My current guy jumped till he was 21, and now I just do dressage with him at 23. And trails.
my first heart horse, Dutch WB mare; 19 jumping around 2’6 - 2’9 courses with her eyes closed. jumper through and though, such speed and she really took you to the fence and made adjustments when you were too scared or dumb to make them yourself.
she had low mileage in her early double digit years as she was crash and burned as a young horse in Europe, imported as a broodmare, then restarted in her mid teens and was a WONDERFUL school master. Gah I am tearing up looking at this photo. She was my adult re-rider love beyond love.
I think she is limited to flatting and crosspoles now at… 25? I am tall, she’s 16.1ish. My dream horse is still modeled after her. A thick 16.1h+, WB mare, dark bay with chrome - forward ride, jump hunting, but also nice enough to throw a decent 2nd level + Dressage test.
He’s gorgeous! My 1.30m jumper told the animal communicator that he won’t be in his prime until he’s 20. 
I can only hope he’s right!
Agree! My friend Caroline McClung (Dowd) did Badminton with her 18 year old mare Lazy Dot back when eventing was a true 3 Day.
Agree that it is less about age and more about fitness, conditioning, maintenance, and helping the horse feel his best.
My 18 year old still does 1m classes with me and we jump around 3’-3’6 at home a few times a month. We are careful about over jumping and he only shows 3-4x a year. It’s all about maintaining!
Supposedly my guy was a tad bit feral in his younger days. I always say I wish he was 10 (or 15!) years younger, but I’m not sure I would be able to ride him 
What a fun resurrected thread!
No one better tell my 22yo OTTB that he’s heading into “old” territory! He just carried my teen daughter over her first 1.40m jumps at home! Also took her into her first ever 1.10m and 1.15m classes last summer and won every class he set foot in except for the one where she went off course. He did his last big FEI prix at the age of 19, I think? Would have kept going (there was zero reason to step down) except Covid hit and the closest 1.40m+ classes were 18 hours away. Wouldn’t be surprised if he stepped up to the 1.20 and maybe even 1.30 with her this year! Love the old campaigners that love their jobs!
