I just wantto let you know that it is proven and confirmed through very credibale chinchilla newsletters that rats carry ( domestic and wild) diseases that they have in their body that never make them sick but they will give to a chinchilla. I have a pet rat, and bred lines of them before I got into chins, and now since I have ONE, I keep him in a different room on the other side of the house, and to be safe, sanatize my hands with germ killer everytime I handle him. He gets baths regularly, but I wont put my chins at risk either way. A vet will also tell you this. Some rats can be placed next to a chin in a cage if it is far enough they cannot put their noses or mouths through the bars and touch each other, but rats also leak a substance called prophoryn, I am sure I spelled it wrong but thats how it sounds, it most of the time if it builds up looks like blood. it is red substance and more visable on light eyed and colored rats, leaks more during stress however they all have it. This is also NOT GOOD for chinchillas or any non rat, and they sneeze a lot and it goes everywhere, although we cant see with the naked eye. Rats often succomb to respatory diseases, usually because they are rats and do not have a long life span, but I would be concerned with a chinchilla near as who knows which ones are contagious and how they will exhibit symtoms in the chinchilla if the chinchilla does get the disease or sickness?