Don't let my "name" fool ya, I do also have a black lab/boxer mix who barely plays. She is going on 6 and for the first five years she never played. Mellow, lazy, laid back...

Now that we have the two cats, she plays with their toys. Now we can't convince her she isn't a big cat and that tennis balls and squeeky toys are for her. Nothing like seeing an 80 lb dog prance with a tiny little catnip mouse.

I think in her case, she didn't understand the idea of playing???