We leave them at room temperature after pulling out of the freezer for 24 hours (or overnight sometimes only 16 hours). Then we place them on a warm UTH or other heat pad for about 1 hour and then feed away. You can also warm them with a hair dryer if you don't have a large number of them. This way seems to thaw them slowly enough that they don't get slightly cooked or stomach ruptures.
Yep couple of feet of 11" flexwatt, dimmer, and a rag towel makes a great rat warmer..
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