We got this rat from the Humane Society a few months ago, and she seems healthy–eats well, friendly, bright shiny eyes, chubby. But she’s developed a bare spot on her chest, and today I notice that her legs are also a bit bare.
The skin doesn’t look inflamed–just nekkid. She doesn’t seem to be scratching or anything.
I googled it and found references to skin mites (although it sounds like I should be seeing some skin irritation if that’s the case) and advice to take her to the vet. But in the meantime, has anyone seen anything like this?
I’m a bit concerned because my friend had a ferret who lost its hair, and it turned out to have a fatal tumor. 
Thanks,
~karol
Try looking for “ratlist” or RMCA on the net. We have found their information helpful.
I will come back later with the address.