Rat Diseases

Question
QUESTION: Hey,
 I have two female dumbo rats named Sierra and Jocelyn.  Jocelyn tends to stay in their little nest in the corner most of the day and will come out sometimes (she is really sweet, just the more quiet of the two).  Sierra tends to be right at the door to the cage when I open it, brings food to Jocie sometimes, generally the more dominant/protective one -- although she never hurts Jocie.  My rats are hooded rats -- they are white with a brown/black hood.  Awhile ago I saw a brown spot on Sierra's neck that hadn't been there before.  I didn't think anything of it, but now she is balding (in patches) on the top of her neck and now has brown flecks on her body.  She's pretty skinny too.  Jocie is fine and healthy, glossy fur, clean body, good weight.  I'm getting concerned and have no idea whats wrong.  If it were the food/bedding/cage/water etc i would think both would be sick.  If either one would get sick I would have assumed Jocie.  I've had them for almost a year.  We also have cats that like to go up the the cage and the rats and cats sniff each other through the cage.  Could Sierra have picked up something from them?  I don't know what to change or do -- do you have any idea what's wrong?

ANSWER: Being that your other rat is not exhibiting the same signs as Sierra may have an allergy related to food. It is very common to find a rat that needs less protein . I found a great website that gives step by step guide to checking off causes to find what is wrong with your rat. It will take time to see results so be patient with that. I hope that this helps.

http://www.dapper.com.au/articles.htm#itchy

This website also is a good source of information:
http://www.ratfanclub.org/diet.html

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QUESTION: Great, thank you, I will try that!  Today I held Jocie and I found some little red dots all over the upper part of her back.  Could they be sores? Mites?  The first step in getting what Sierra has?

Answer
Parasitic infections have bugged many a rat. Mites can enter your home via wood shavings or other wood toys or chewing blocks in your rat's cage. These pesky critters may show up as little red dots on the skin, and can cause your pet a lot of distress. Animals infested with mites tend to scratch constantly, and commonly have scabs on their face, hind legs, back and shoulders. A trip to the veterinarian is in order to clear up the infestation, and you may have to bathe your pet and treat the cage and surrounding area, too.