Playful behavior.

Question
Recently I've had to integrate a pit mix with a jack russell mix.  Both are rescues and were fairly young when we got them.  They've had a few fights, but each time I have disciplined both of them and that has corrected the problem.  However, they exhibit some behaviors that are strange.  They will nipple and chew on each other around the ears and neck as well as chase each other in a sort of "cat and mouse" game.  All of it seems to be playful and they both seem to enjoy the activity.  Is this normal?

Answer
You've got your hands full....two very assertive, independent tough breeds.  You seem to have established full rank over these two so congratulations!  ALL "play" behavior is rank related; these two appear to be testing one another in a manner that is acceptable to you as "pack leader".  I think you need to closely observe these two: who greets you first? who goes in and out of doorways first? who is first to the food bowl and backs off when the other approaches? who is "winning" these "games"?  Look closely at body language: Ears (if ears are forward and erect, that's an excited and dominant pose; if ears are flat back, that's a fear or submissive posture);  Tails (if tails are up and over, and yes even the JRT with a docked tail has a tail posture, that's a confident or dominant posture; if tails are body length and wagging slowly, that's a friendly gesture; if tails are low and tucked under, that's a submissive or fearful posture);  Eyes (if you see a lot of white flashing in the eye, that is a submissive signal);  Hackles (if hackles are raised, that's fear or dominance).  You might benefit from reading Turid Rugas' book on "calming signals" so that you can fully evaluate what's going on.  If this sort of behavior makes you uncomfortable, redirect it.  Call both dogs and make each one 'sit' for a treat or praise.  Do not tolerate what you don't like.  You are the 'pack leader'.