Hey, I just had a thought, I dont know these things yet, (I am currently studying as a Vet Nurse) but is the pony getting worked AT ALL? Because if he is just standing around it might be causing him to develop oedema in his legs (that is pooling of the blood in the legs from standing around) you sometimes see it in horses that are boxed alot, Im just wondering if it isnt to reduce the blood flow to his legs, therefore reducing the swelling maybe? Hehehe just a guess, but when ya find out please let us all know..hehe