I adopted a baby boy rat, grover, around june of this year. He was super shy and gentle, introductions didn't go to plan [bath tub meet-up method] and my rat bert attacked him viciously. bert began bullying ernie, my other rat, so I had 2 rats that got along fine and 1 aggressor. I got rid of bert, but baby grover was stuck with a serious facial bite wound and several deep scratches from their fight [it was very short - it looked like a tornado. but lots of damage was done.] I tended to grover to my best ability, and everything seemed fine. His big bite facial wound healed really well, and he seemed happy and at peace at last. I apparently missed one of the wounds, which turned into an abscess, and making him take antibiotics wasn't any fun. Eventually it popped on it's own, so I was on the clock with him again cleaning his wound until it closed fully. Health wise, he now has a clean slate. He was still so shy and timid, but ernie was very sweet to grover no matter what - even letting him dominate some of their tussles.
I have them out every day in a large play area, and a critter nation cage. I see them a lot and grover had been everyones favorite because of how cute his shy personality was. [by shy i mean he was always happier in my arms than anywhere else]. Ernie is a very open social lil guy, no fears about anything. Ernie is what I consider a model rat in terms of behavior, he's a total social sweetie.
Grover within the past 24 hours has bitten me and my boyfriend [he's known my bf since he's been brought home.] He's drawn blood on my boyfriend, and he didn't bite me until right before this post. He didn't bite me hard enough to bleed, but I can feel the burning sensation as I type. He's entering a teenager age, his fur is roughening up and he's getting bigger, so I'm assuming it's that and hoping for the best adjustment. But I'm just really concerned what I should do if it continues.. He hasn't shown any aggression towards ernie, though.