Sudden aggression- help?

[Dazydaizee]

My 9 month old male, Teddy, suddenly began acting strangely this afternoon. He is normally a lower rat in the pack and doesn't tend to start fights. We did recently (a few days ago) finally cage my two new boys with the three older boys. Teddy has been getting along fine, aside from an occasional scuffle which is to be expected.

Just a few minutes ago I noticed him initiate a fight with Cheeto, the biggest, most dominant rat in the cage. Prior to this he was walking around the cage all puffed up. After the scuffle he went to the bottom of the cage and stayed puffed up, he wouldn't calm down. My boyfriend tried to pick him up (usually in this case if we go slowly we can calm them down and don't get bit, though we know it's a risk if they're worked up). Well Teddy turned and bit Scott hard and drew blood. I picked him up in a towel and looked him over. No obvious cuts or signs of injury. I set him back down and he continued to remain puffed and VERY sensitive.. if we'd go near him he'd turn fast and walk fast towards us, I presume to bite.

Cheeto came down a few minutes later and Teddy backed into a corner. He kept stepping toward Cheeto and squeaking at him, threatening him, chattering his teeth and drooling. Cheeto didn't get too close. We sectioned Teddy off in the bottom section of the cage and he started walking around like he was uncomfortable. He kept laying down and looking not quite right. Now he's walking around and kind of brushing his back against things, then laying down uncomfortable...

What could be wrong? I will take him to the vet tomorrow if he's still the same (and sooner if he gets worse).. but I know his aggression is likely the result of not feeling well.. but any idea as to what could be causing it so suddenly in such a young rat with no signs of injury?

I appreciate any help...

[Dazydaizee]

Okay.. I took him out and did a basic check.. neurologically he seems okay, he can place his feet.. no pain elicited when I felt his back or stomach.. no obvious masses felt...
I let him walk on the bed and he did this normally.

I put him back in the cage and he puffed up right away. I watched him and he seems to be acting VERY territorial. The rubbing he's doing is with his back end on objects and he's rubbing his hands on the ground. He is sniffing every little spot and walking around almost like he's urine marking, though I see nothing coming out... WHY is he suddenly acting this way?

[lilspaz68]

Overload of hormones...hormonal aggression, and the age is right for it to show up tooan.   Rubbing/digging with the front paws and rubbing of sides/flanks on objects (there's a gland there) is marking his territory.  All very classic symptoms.  Be careful not to touch his butt and back as this is an "attack" to a hormonal male, he's not himself and has no real control over his rages.  He also sounds very defensive as well, which makes it a lot worse...backing into corners and chattering his teeth all sound like subordinate behaviour.  Poor boy.

He may need a neuter.

[JR1030]

I agree with the neuter...it will help him calm down, and he'll be happier that way.

[Dazydaizee]

I took him to work with me at the vet's office today. The vet agreed that it seems purely behavioral and recommended neuter... so we did it this morning and he's recovering now. Thanks for the replies. I was just worried where it came on so suddenly. I know that these are all signs of aggression and marking behaviors.. I just wondered if there was a health issue because of the sudden onset.
His brother, Michael, is scheduled to be neutered next week, too.. so hopefully everyone will finally settle down!

[JR1030]

I think that was a great decision.  Sometimes if a rat continues on with aggressive behavior for a long time, even a neuter doesn't help because it's become behavioral in addition to hormonal.  Sounds like you nipped it in the bud (so to speak  ) and I think he should calm right down.