Levi has had so many scabs all over him since I got him two weeks ago, and I don't know how to tell whether they're from his playing with my sister's dog, 

ocket, or something else. I know they play rough and grab and hang on to whatever their teeth manage to come into contact with, but these scabs keep getting ripped open and he's got bald patches where they have been ripped off! He has about three to four 1cm x 1-2cm ones on his right shoulder down to his leg, and a couple on his cheeks and around his neck. Should I assume these are just from playing? He hasn't shown any irritation, no itching or anything...But they keep bothering me, coz it seems his old ones aren't healing, and he's just gathering new ones...They live together so it's a bit of a problem trying to separate them to see if they stop coming....Any ideas?