Thawing Mice and Rats in a Refrigerator
The USDA uses 8-10 hours per 1 pound of meat as a general guideline; a mouse can be expected to thaw in 2 hours, a rat in 4-5 hours. Fail safe rule: place frozen rodents in a refrigerator for overnight thawing and use them the following day.
Make sure your snake is adequately hydrated. Snakes that are dehydrated may be less likely to accept frozen food. Always provide a clean water dish and ensure the humidity levels in the enclosure are appropriate for your snake's species.