Dead gerbil

Question
I'm devistated! My husband woke me at 5am this morning and told me that our gerbil (dippy) was having trouble breathing.  I took her out of her cage and noticed that her abdomen was bloated.  Her mouth was hanging open and she seemed to be gasping for breath. I put her back in her cage and her balance seemed to off also.  I wasn't sure what was wrong with her, so I told my husband that I would call in the morning and get some answers, however, sadly, she is dead this morning, belly-up in her cage.  I don't know what happened!! She seemed fine yesterday during the day!  I am also concerened because this is the second hamster/gerbil that we have had die in this way in the past 6 months! We had a hamster that we got from the pet store and he died after 3 months, we found him belly-up with a bloated abdomen as well.  We threw out that cage and bought a new one when dippy was given to us by a friend.  The only thing that we kept was the food that was still in the bag (which we also used to dippy). When dippy was given to us she had a terrible sore on her stomach between her back legs from biting herself (which I can only assume was stress related) but we nursed her back to health, she was doing great, and now this.  What happened??!! I don't understand, I have had hamsters and gerbils all of my life and i've never seen anything like this!  Please help!

Answer
Hello Faith,
I am so sorry for your loss, but I must say that there was nothing you could do to prevent this. From someone that has worked in a pet store for a while I must say this. Not all of the pets are healthy inside and out. Some will have diseases or problems that won't show for several months. The clean bill of health that you see guaranteed from pet stores generally means that many diseases that could be harmful to humans has been ruled out and they show no signs of illness in their care at the day of sale.
That being said, sometimes you will pick a small animal that appears healthy, but may have something internally wrong that won't show up for a while. With small animals it's hard to know what can be wrong with them internally. Many people think that it's their fault everytime they buy a small animal and they die suddenly, but in many cases there's nothing that could have been done. It sounds like your gerbil may have had some time of intestinal problem and/or respiratory problems arise. Small animals die very quickly when the first signs of illness appear and they will appear suddenly and out of no where.
I can't give an honest answer on the true cause of death, and for that I am sorry, but sometimes you will have the misfortune to receive an animal that may not be 100% healthy inside and out.