I was told that one of the new horses I'm working with, Houdini, stocks up sometimes. I've never worked with a horse who had this happen I
believe it has something to do with the horse's legs swelling up? Could someone please explain more thoroughly what this entails, what causes it, and what to do to prevent/help it?
Stocking up does refer to a condition where the horses legs, most notable the hind legs in around the fetlock area, will swell up.
It's caused by an unconditioned or inactive horse who is suddenly put to exercise.
More turn out time will help to improve his stocked up condition, and daily exercise will help to prevent it in the future.