For those of you that leave there babies in crates for a few hours while at work, what type of chews do you use? Kong w/treats inside, or some type of edible chew? If the edible type, do you give this to them everyday? I'm just kinda sketchy with all those chews due to chemicals. Any natural chew? I don't really want to give my chat a Knuckle bone inside his crate. Or maybe it's best? By the way, he is on pure raw.