Kim,
Cat poop is loaded with PROTEIN! *bg* Their diet is more meat-based than dogs, so when they go, it's loaded with 'pro'. If your dog hasn't ever eaten cat crap before, it might be an indication that its protein levels are outta whack. You can have blood tests done pretty easily, but even easier is to just give them some cooked chicken with meals to up their blood proteins.

And, yeah, you're right about the catnip.