I went against all that is good in the world (to my nose at least) and got 1.1 mice. I want to start a small colony to supplement things when I have hatchling BPs that need to eat in the coming year. Well, I am using the pine pellet bedding.. there is no bad, strong mouse urine odor like I had with shavings in the past! I only got 1.1 for now.. But if this is a way to keep that urine odor down.. I just might breed more mice.