Playing or fighting

Question
Hello,

I have two male rats that I rescued about a year ago. Can you tell me is this playing or fighting?

 They will chase each other around the cage, stand on their hind legs, then they jump at each other like there attacking each other. Or, one is on top of the other(it looks like the one on the bottom is frozen)holding him down, and the noise they make sounds like little screams. I usually stop them because it sounds like there mad, but is this there way of playing or are they fighting and should I continue to stop them? Hope this make sense.

Answer
 It could be playing or fighting; rats usually 'play-fight' for fun and sometimes they will squeak like that even if they are just playing.  The only way you can tell if they are being too mean to each other is if their fur is puffed up, they are hissing or huffing at each other, are really screaming loud, or are drawing blood.  Little squeaks are all right and are normal when rats play, and if they are playing they probably won't have their fur puffed up.  If you pick them up when they are doing it they will not mind if they are playing, but if they are fighting they may run away, be scared of you, or even try to bite at you, thinking you are another rat come to join the fight.  If they are just playing they may even let you wrestle with them with your hand.

 If they are fighting, I wouldn't stop them unless they are constantly doing it or are hurting each other.  Rats often have petty squabbles over food and territory and they need to work out their problems on their own.  Only separate them if they are causing injury.

 I hope that helps to answer your question, good luck with your rats!