My mom has a male Mandarin that had to be removed from the other ducks because they beat him up badly. His feathers are growing back but I guess he bleeds easily and just generally doesn't look well despite being on his own. Is there some kind of disease that he may have? All of the other ducks are healthy, there are Mandarin's and call duck crosses that he was caged with. He had been fine with them for a year and then they started picing on him bad.