Is this horse going to stay sound for a long career, and most especially for the job I want him to do? Its an important question, because it doesn’t matter how amazing the horse is or how much you like him if he’s not sound enough to do much more than look pretty in a stall. So first off, the news you don’t want to hear – soundness is at best difficult to predict in a young horse. There are horses with truly awful x-rays that never have a day of unsoundness, and there are horses with perfect x-rays that never make it into a serious career. There are only a couple of genetic traits that have been linked to unsoundness – DSLD and OCDs coming to mind first – and yet even they have complicated inheritance, with environment affecting whether the genes will ever express themselves.
So what can you do? First, never underestimate the importance of a vetting and the opinion of a trusted vet. When in doubt, send the x-rays to a second vet for a second opinion. Do your research; some things can be fixed and/or lived with, and some you should run away from because they are likely to be a recurrent issue. Some of these things may not be problematic for a trail horse, but would be career-enders for an “A” show jumper, so make sure you communicate what you’re hoping to do with the horse to your vet.
And then put a lot of thought into how you raise your young horse. There are two things that can most prominently effect your younger’s development; turnout and diet. Turnout is not only linked to muscular development and social development, but studies have linked increased bone density to moderate exercise in young horses. “Moderate exercise” is meant to reflect the type of exercise a young horse would experience turned out, rather than ridden or lounged. Too much lateral (turning) work puts wear-and-tear on joints more easily than work in straight lines, and riding puts wear on the back — one of the last places in the horse’s body to finish developing. Ponying a young horse next to an older, wiser horse is a fine alternative if large turnout isn’t in the cards, and it has the added benefit of the youngster copying the ways of the old, wise hen.
Now onto diet; and this is an important one. Spikes in sugar intake and imbalances in the diet have been linked to higher incidence of OCDs and lower numbers of OCDs healing. In other words – diet can affect the likelihood of your youngster developing an OCD in the first place, and the likelihood of that OCD then healing successfully. Notice I said spikes in intake; even the “low starch” grains have a great deal more sugar in them, pound for pound, than hay. It’s easy to jump immediately to the idea of cutting all grain out of your horse’s diet, but remember – diet imbalances have also been linked to OCDs. That includes calcium levels that are too high, levels that are too low, calcium to phosphorus ratios outside of the optimum 1:1… the list goes. on. Which means that, before you jump straight to cutting grain out of your horse’s diet, make sure the nutrients it was providing will be provided in a different way.
Beyond that, don’t override your horse too young. Which is to say that there is a world of difference between riding a 3 year old about 20 minutes a ride 3-4 times a week for 30 days out of his entire three-year-old year, and riding him for an hour 3-4 times a week for the entire year, plus horse shows on the weekends. Remember that bit about moderate exercise and bone development? Here it comes into play again. Moderate exercise is an entirely different conversation from heavy exercise, so keep this in mind when you’re considering what to do with your youngster during his developing years.