In answer to the question of "How do I know if they're too rough at play?",
my answer would be to carefully examine the backs of their necks for any
sign of scabbing or bleeding.
 
When my Felix started getting adrenal disease, his behavior toward Mikey,
who'd been his best buddy for a year, changed - Felix started launching
full-on assaults and you could tell by the (minor) damage on poor Mikey's
neck that it was going too far.
 
Good thing Mikey was both bigger and a very mellow dude, or things could
have gotten really bad.  As is, Felix didn't survive adrenal surgery; his
was one of the rare cases where the tumors "jumped" to other organs.
 
Anyways, if everyone's scruffs are in good shape, just chalk it up to
typical rough ferret play and enjoy.
 
 - Jim
[Posted in FML issue 1790]