rat is warm with red ears

Question
Hi Sandra, I've written you before and you've had such good advice. We have
two rats -- both about 4 months old. One, Chocolate, suddenly feels warm
and her ears look redder than usual (all over). She's usually very playful and
energetic, but suddenly doesn't want to move much. Almost in frozen
positions at times. Very snuggly and calm. You've recommended a great vet
here in France, but thought I'd check with you first. Thanks! Wendy

Answer
Hi Wendy

Usually a sick rat is cool to the touch rather than warm. Rats dont usually get a fever because they lose so much body temp from their tail.

Normal body temp is around 100 or so, even 101 being normal.
The red ears may indicate being in heat to be honest.  

Did something scare her recently?  Is she eating and drinking? Is she weak?