Try what we're doing with our male [10 years old, used to only take white live mice, now taking f/t rats]. We place the f/t rat in a baggie, but leave the baggie open. Place it on the screen top [if you're in a tank or next to the "vent" holes on tub (is that how it works? I don't have tubs so I'm not sure)] and let it air thaw. Yes, it takes a long time, but if you're buying good quality f/t prey it shouldn't smell. If you use lights, after it gets to room temperature place either the head or whole rat under the dome. If you exclusively use UTH like most people here do, place it somewhere warm or blast it with a hair dryer for a while. The rat's head should be warmer to the touch and the rest of the body should be warm to the touch, with the head hotter than the rest of the body. Leaving the rat on top of the screen if you're in a tank or somewhere with a tub where the scent of the rat can get into the tub/tank lets the smell get into the enclosure and gets the snakies hyped for the meal. Our female goes nuts and just stares at the rat with her head and neck out of her hide until we open the tank and our male peeks just his nose out like, "you brought me food?"