OK, our BP is on F/T and when we were feeding fuzzies there were no problems. We defrost the mouse in a pot of hot (not boiling) water for a few minutes until nice and soft and warm throughout. This was how we were taught to do it by the store that sold us the feeders. Since we have moved up to the next size mouse, every time we feed him the belly of the mouse bursts open as soon as he strikes. He ends up rolling around in a pool of mouse guts/blood while eating and we then have to clean him off with a wet cloth after dinner. Are we doing something wrong and is there any way to prevent this?