My Rat seems to have a growth, on its rear.

Question
Hey there, my name is kyle, and im desperatly looking for some help in regards to my 8-10 month old wharf rat, i bought her( as i will call for now ) at a pet shop, things are great, but about 3 weeks ago, i noticed she had like 2 bumps on her back side just below, her anus,  im a little concerned if this could be a tumor or if it could be a set of testicles and infact my rat could be a boy, they stick out quite far, there like 2 little mountains which shoot right back, they swell up and go down, could u please give me some insite in to this, as i do not want to have to put my sweet bella down if she truly isnt sick :(

Answer
 Well I'm not too familiar with wharf rats, but in Norway rats (the rats commonly kept as pets) the testicles are usually very obvious starting at 6 weeks of age or earlier.  Here are some pictures of how to tell a boy rat from a girl which may give you some more information on whether they are testes or something else:

http://www.thefunmouse.com/info/sexing.cfm
http://www.ratz.co.uk/sexingrats.html
http://www.afrma.org/sexing101.htm

 If they are not testes, they are either swollen lymph nodes or tumors.  An exam by a veterinarian will let you know for sure what they are.  Many veterinarians have a lower examination fee for rats, generally between $30 and $45, and if your vet feels they are a health problem he or she will be able to aspirate them to find out exactly what they are and advise you on treatment options.  If you could send me a picture I may be able to give you some more insight into this, my email is info@evergreenrattery.com

 Hope this helps you, good luck with your rat!