Fighting or Playing

I have two male cats that are both altered. Bit is a year old and Scratch is around 9 months. They get along most of the day, but every now and then Bit jumps on Scratch's back and holds him by the scruff of his neck. Scratch will growl and hiss and the two will look like they are getting into a cat fight. When this happens Scratch will run and hide under the couch. Then like clock work the two will calm down and fall asleep next to each other. They will sometimes groom each other. I am trying to figure out if I should be breaking up these growling matches, or if they are just playing rough.

What you are seeing is classic dominance behavior. When Bit grabs Scratch's neck he is exhibiting his dominance over Scratch. It is Bit's way of reminding Scratch that he (Bit) is the alpha cat. While Scratch surely hates this, it is not dangerous and does not need to be stopped.

Thank you so much. It's been bugging me for the last few days.