I assume a sprinter is better younger while a dressage horse needs approx 8 years of training and development to reach the top of the sport.
I read that the best offspring of Stallions are their earlier ones, so prime for a breeding stallion is likely to be before he's proved himself. A breeding mare would probably benefit from a year or two extra development for her prime.
Dependent on breed and under 15.2 it would be in its prime from 6 to 16. Over 15.2, 8 to 16 would be my view of in their prime, soundness dictating of course.
No horse is skeletally mature until approx 8 .. so anything younger wont be in their prime.. they might well be pushed to seem like they are but they will just breakdown and not really reach their prime.. pushing an immature horse means it will never reach its prime or potential. I would say anything from about 12 to even 20 if they haven't been pushed.
I was looking at my gelding this morning cantering in the fields, thinking how he’s now in his prime years.
He’s 9 this may, and he’s almost lost his coltish mindset!...his body structure has developed slowly and solidly for so long - its been amazing to witness. He’d be really athletic looking if muscles more developed. He’s got a lovely frame now.
So its for me, the mind of the horse being mature enough to think sensibly, aswell as the body being developed well.
9’s a good start to the prime years.
I always say 9ish to 16ish but I think it depends so much on the horse - their personality and cooperativeness, their sense of humour, their early life and lifestyle, their emotional well-being, etc! And of course, a bit of luck too ... My "best" dressage horse never became my best dressage horse because of ringbone when she was 9. She had so much promise, but we had to retire her for hacking at 12 and lost her at 18
My "youngster" (traddie cob) is now 8..... or very soon anyway, god-alone-knows when exactly she was spawned, but it's gotta be around now'ish. Guess I'll have to stop referring to her as the "baby" of the herd now though! Blimey where's the time gone. I feel that now she should have finished growing, we should be coming into "prime" time for her.
My other horse (cob) is 10yo. I would regard around that age as being in a horse's "prime". Sadly she can't be, as she has a headshaking issue - trigeminal nerve - which means that she can't be ridden. Only the other day I said to someone that she should be in her "prime" now........ poor old gal.
I would regard prime-time for an ordinary Riding Club/Pony Club/Hacking or Hunting pony or horse to be around the time from say about 8 through to "veteran" age at say 16yo. Probably around 10 - 12 'ish would be what I would regard as the Golden Years.