[Prime Choice]

I didn't know that. Most of my rats grew large tumors shortly before they died, I had no idea this was due to any sort of breeding patterns.

Yup. Sad, but true. If your ratties were girls, chances are pretty good that the tumors were mammary cancer. Very common. I've seen about 2 dozen cases of it in the ones I've rescued. Highly treatable, but it does have something of a recurrence rate.

I've also had a few rats who also had some rare sarcomas (cancer in the connective tissues). Very nasty, very malignant, very metastatic. Having them put down was a severe mercy.

[Serb5150]

My rats were all girls. One had a tumor on her neck, another had one on her belly that I had just noticed forming before she died very shorly afterward. They didn't seem to be in any pain whatsoever - they would run around, play, and eat like little piggies until they died.

I did have one rat with no external signs whatsoever of tumors or illness, that suddenly died one day while I was at work. The only sign on her body I could find to explain what happened was a little of blood coming out of her rear end... any idea what that could have been?