A decent colony of roaches (1000-3000) will eat a full grown mouse in 12hrs. A colony of 500 growers will eat a fuzzie in 12hrs. No smell and they really go mad over it, fighting each other to get at it. No mess, they eat all the bones and most of the hair. I'd say chances of an illness transfering from a mouse to a roach to a lizard would be minimal. There's no particular reason to do it (unless you want to.) If I have a snake refuse a feed, I have nothing else to give the mouse to, so I feed it to the woodies.