Sometimes the best thing for an agressive rat is to have it put down, especially if it is NOT neutered. The best thing for the animal would be to put it to sleep, where it could at least die peacefully, the way they are meant to.


But first try neutering, although you do need to know the risks involved. The safest age for neaturing is around 2 weeks of age, after that the chance of bleeding to death etc. goes up. How old is the rat? Age in ratties is something you always need to consider before they are put under anesthesia.


Some rats are just agressive, or cage agressive as Wolfchan said. Since it sounds as if he was the only one growing up, that is why he does not like other rats. Do not buy a rat unless you are willing to get a friend of the same sex, it can literally drive them crazy from lack of socialization, and with you in school and without a friend, he is probably very lonely.


Before you get any animal you need to do your research. You diet is off, which also may be contributing to his mood swings. I would go to the RFC and ask for advise. Good luck!