12/06/2024
Friday Fact-
To the naked eye, horses are mature at 2-3 years of age. X-rays also show that their bones are fully formed at this time, which has led to the common practice of starting horses under saddle at this age and is even the basis for racing horses of this age. However, post-mortem examinations of equine skeletons from horses that died at a variety of ages have found that their spinal processes (parts of their vertebrae that connect to ligaments and tendons) are not fully formed until between 4.9 and 7.2 years depending on the individual horse and specific region of the spine. Radiographs have a hard time capturing detailed images of the spinal processes, due to how fine they are, so radiographic studies used to determine the right age to start horses may not be that reliable.
That being said, there is also a lot of data that shows free movement and even training under saddle in horses 3 and younger increases their resilience to tendon and ligament injuries in their legs. All of this to say, exercise is helpful and very important for developing young equines. But pushing them up the levels.. probably not so much. And continual training without a rider is probably equally, if not more important for their development.
I’ve been dismayed while marketing a 5 year old horse for sale at how many people have been confused as to why he was not started until 4 years old, and why he’s barely been jumped, and why his gaits under saddle are still developing. It’s certainly hard to compete with people selling 5 year olds with tons of experience jumping 3’+ courses or showing 3rd level. But there are no studies yet telling us what the effect of intense training in various disciplines at 4 or 5 years old is on a horse’s overall career, and such a study is badly needed. Just because a horse *can* do something, doesn’t mean he should be asked to.
https://avmajournals.avma.org/downloadpdf/view/journals/ajvr/58/10/ajvr.1997.58.10.1083.pdf
Thanks to flatlands photography for this gorgeous photo of my 5 yo gelding, Nash! He has shown all the scope and bravery to move up the levels and jumps 3’6 gates for fun in turnout, but he will be staying at 2’6 for at least another year.