I have always used sterilized bones. They are good because they are not greasy but you have to be careful if you have an aggressive chewer. The dog can fracture teeth on them. Also I have had one bone break in halve right down the middle, when they do that get another one because they are too sharp and can cut their lips.I had just bought it, too. That has only happened to me once in eight years so it may have been a fluke thing. If the dog drops one on your foot or if you step on one in the dark with bare feet it is not the most pleasant feeling but other than that my lab always goes for them.