Rat Feet

Question
My pet rat has been doing fine up until about two weeks ago.  Since then, he's been lazing around and dragging his feet when I let him loose. He's always been a heavy breather, but his breathing seems labored even for him lately.  I just spent about $1200 on two rat surgeries in the past 6 months, so I can't really afford another trip to the vet.  Do you know what this is?  If so, do you have any suggestions about how to deal with it?  Thank you.

Answer
Sounds like heart problems. Sometimes a rat will lose the ability to walk when they have heart disease.  Thromboembolisms (blood clots) can be the cause of his hind leg paralysis and is often seen in heart disease.  The fact he is breathing heavy also means he may have heart problems.  Does he hang his head over the shelf or ledge of his cage? Do his sides sink in when he breathes? Is he eating?
Losing weight?  How old is he?

Also, if you spent that much money on two surgeries, thats super steep....what kind of surgery was done?  Is your vet a board certified exotic companion mammal vet or just a general vet that sees exotics?