I am frequently asked if the same principles for evaluating conformation apply to young horses. Yes, they do, but with a caveat: one has to already be good at analyzing adult horses plus understand how youngsters grow.

My advice is to make sure you become proficient at analyzing adult horses before relying on your accuracy with weanlings or yearlings. What if the youngster is butt high? Do you know what is causing him/her to be butt high? Do you know for sure that all the bones in his hindquarters are growing at the same rate? If the youngster is higher behind, you already accept that all the bones don’t grow at the same rate, right? Otherwise they wouldn’t go through the growth phases of butt high, level, butt high, level, etc.

So, expanding on that, what if the youngster is higher in the hindquarters because he/she is growing femur length? Appearances may lead you to believe that Junior has the same length to the femur side and ilium side now, but when the other bones lengthen, Junior will likely be shorter on the femur side than the ilium side. Not a good thing.

This previously-published article (conform[2]) , although about yearling Thoroughbreds, is intended to show you how some aspects of functional conformation can be determined and how those relate to the athleticism and longevity of the horse as an adult.