Most of mine have been from pet stores and I've have bad luck with the breeder I got my rats from before. I got 4 rats from her, 2 each time and all of them passed away before they were a year old. This just shows you never can tell with some things. I guess I just had bad luck with that breeder but a breeder rat could have just as many health problems and such as a pet store rat. Like I said, I've have good luck with pet store rats and extremely bad luck with breeder rats. =x