We have a horse farm and last night one of our older horses died. While we were waiting for the man to come with the machinery to dig a grave, she was in her paddock covered with a tarp. Our Pit Bull went over to her and bit her face then left. After our mare was buried he went back out and pooped on the grave in several places. He also was digging where the blood was from when he bit her face. He has never shown aggression to any of our horses and has a very sweet nature. We don't know quite what to make of this behavior and wonder if anyone here has experienced a similar reaction from their dog. Any suggestions would be greatly appreciated.