HELP! am really worried about 2 of my rats - Moz and Cooper. over the past few days have noticed some red marks on their skin. coopers coat looks a little thin and poor Moz even has a couple of bald spots around the back of his neck. however Biffys coat looks perfectly fine - really full and no red marks. am wondering if he is over-grooming the other two? they are only about 2 months old and he is already noticably bigger than them and saw the other night he is fairly rough when he grooms them. they all feed fine and dont fight, really dont want to have to split them up please help - is the first time have owned rats.