Its hard to tell from the pictures but I don't think he is any real distress. My horse lost about 150# when we moved him because of mares. He loves the ladies and if he has a choice between grazing and chasing the girls, girls win every time. The good news with that is, he needed some weight off of him anyways! I would up his hay and see about putting him in a better pasture if the one he is in is lacking. Get him away from the girls if you can. Grains will help but only forage will actually put the weight on him. Good luck!