Is it normal for a horse to sweat slightly when he is stood in the stable? I brought Tarragon in yesterday and left him to eat a haynet in his stable while I potted about. I came to groom him about 45 mins later and noticed he was slightly damp behind his ears and in between his legs. He was stood quite calmly, was tucking away on his haynet and he had passed droppings. He does have a very thick coat at the moment (he is a highland) and it was a fairly mild day but can a horse really sweat up whilst stood still?