Well, I put mine in hot water until they're all squooshy all the way through and they hold their warmth for a couple minutes outside of the sink - make sure the belly doesn't feel chilly. For my med rats, I leave them in for about half an hour. So, go by that, hehe.
Wet rats can be good for snakes. Gives them extra hydration and can, apparently, relieve constipation.
BUT if they don't like wet rats, just put them in the sink in a plastic bag.
If they've never eaten f/t before, make sure the rat's warm when you feed it. Can can "see" the heat. Or try "braining" it - poking it so's the brain's all exposed and smellable to the snake. Also try wiggling it with forceps - the "dancing mouse" routine. Just not too close to their face, or above them. Along the floor.
Yup.
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-Irish
My Snakes