I have a large Orpington rooster that’s 6 years old. He’s got a crack in the very top of his shanks where his skin meets his shank. They are like split open. I can’t figure out why they keep splitting. He also has grape like growths above his skanks. Is this normal? His scales on his legs are large and he’s treated with Ivermectin as is the entire flock. He shouldn’t have leg mites because of his treatments. I’m at a loss as to why his skin keeps splitting. He’s in pain and I’m not sure how to help.