Hmm. I'm still not cleared to post in "Rat Behavior". Here's my post until I can stick it there:
Howdy folks. I just want to precurse by saying I've wanted a pet rat for years, but living situation never permitted. I recently took in a rat from an acquaintance who could no longer care for it. She received the rat second hand as well, so I do not know the rat's age, history, etc. He is a white albino male who appears and acts lively and healthy. There is a minute scar behind his shoulder blade but it seems long healed. When I first got him last week he was incredibly docile. He would let me pick him up with no issue and would sit on my shoulder contentedly. I got him a two foot cage setup with a cave and hammock. A day later he appeared to be settled in and i went to pick him up. Ouch! He bit me quite hard, enough to draw blood. This happened every time I would put my hands near him. I was upset, as this behavior just seemed to spring from nowhere. And it doesn't just occur now when I put my hand near him. If I have my hand anywhere in the cage he will vigorously pursue it like he is defending his nest. If I leave the cage door open he will even sit on the door like a guardian, waiting for me to come close to take a chunk out of my hand. A few days ago he bit me and would not let go for some seconds. This didn't just draw blood, he bit down on the space between my knuckles into muscle and tissue. It's still swollen days later. I've tried to coax him out covering my hands in a shirt, but he will scratch at the shirt (While anchoring his back legs on the wire cage door) as if to expose my flesh for another attack. Once I was able to coax him out, and outside of the cage he is back to his docile old self (If the cage is not in sight. If it is he will desperately try to climb to it). He sat in my hand and licked my arm yesterday. However, as soon as I put him back in the cage he is aggressive again. Out of morbid curiosity, I even presented him a clean tissue, and one that I had stopped my bleeding with from when he had bit me the day before. He only sniffed the clean tissue, but the bloody one he violently ripped back in his cage and tore up. So I guess I feel a bit discouraged. I don't know how to get him acclimated to me. I'm trying to be patient but I am out of ideas. I put an old shirt of mine that I was wearing in his enclosure so he could get used to my scent, but it doesn't appear to have helped yet. He is not neutered. I'd rather not resort to that if it can be helped otherwise. Also, I want to get him a companion as I know rats are social animals, but with his current territorial aggression I am a bit reticent. Advice, Please?