Mazuri and dog food. Not premium dog food either. Premium dog food has more protein, so there is no sense in feeding the "good stuff." Every dog food from Walmart is pretty much only corn and grains, not protein-read the ingredients list (by-product is bones/feathers/feet/hair, not meat). I wouldn't feed my dogs that stuff, but the rats, sure.
I feed dog food just as an additive. They prefer the dog food over the Mazuri, but I probably would to. It's like your favorite fast food compared to a salad, which would you pick?