If you are inexperienced at integrating rats and handling rats, DO NOT attempt this. Experienced rat people know how much force to use, while newbies might apply too little or too much pressure, with tragic results to them or the rat. You might get scared and maybe end up hurting the rattie. Also, ratties are really quick, and many will flip around in a flash to bite the hand.
Alpha rats will do two things to their subordinates (minions), they will flip them over and rub their paws on the minion's chest, between the front paws and/or they will get up on the minion and put their teeth between the shoulder blades. This is why scuffles with alpha can result in injury. When the alpha lays his teeth on the minion, they are suppose to submit but many don't, they get scared and try to run off and this may result in a slice, usually on the neck, the shoulders and back. An exceptionally bad attack can seriously maim or kill the subordinate rat by biting the spine.
So what I do, I mimic the dominance over the instigator. You do this when you catch them in the act of being a bully. Rump rubbing, boxing, are normal behaviors but when you see scuffles, balls of fur flying, this is when you need to intervene.
Be very careful when attempting the pinch, it's very easy for rattie to flip around and bite your hand, remember, he's in a highly stressed state when you are doing the pinch.
With one hand, hold the rat by the base of the tail making sure all four paws are on the ground. With your other hand, grab hold of some skin between the shoulder blades and press the rat down into the floor. He will protest and scream bloody murder but you aren't hurting him, you are simply hurting his pride. Let go after a few seconds of this, just long enough so he gets the message that you are the Alpha. He will usually go sulk, give him a few minutes then pick him up for lots of cuddles. I'm attaching pics so you can see what I mean.
On a girl rat, usually all that is needed is for you to flip her over and with your two fingers rub her chest firmly but not hard.
I've been doing this for a few years now and it's amazing how great it works. The Alpha will understand that he cannot go on attacking the minion when you're there to out-Alpha them. He will also understand that while you're the Alpha, you're not there to hurt him. Of course the real aggressive rats, this won't work, neutering is the only answer.
