ALL puppies "play-bite" and you do need to discourage it. When Higgins would do it, I would say "NO BITING! Just kisses..." and when he would stop, I would praise him. If he didn't stop, all play stopped and I would put him down. He caught on after a few weeks.
Don likes to "play rough" with him and lets him do it now when they are playing.
But it's funny, Higgins NEVER uses his teeth with me! He doesn't do it with anyone else now either. Just Don, and ONLY when Don "gives him permission."
Speaking of giving permission, the best thing Higgins has ever learned is what a friend, who trains her dogs in obedience, taught him (us). We make sure he knows that all his toys are really "ours" by keeping one that he brings to us and very slowly waving it around in the air just out of reach and telling him to "STAY." We praise him while he is staying and we are "teasing" him by keeping the toy in motion just out of reach, but bringing it ever closer to him. Then, after a few seconds, say "OKAY" and letting him grab it. We have gradually stretched out the time to where he will not grab that toy unless we "give him permission", even though it may only be an inch from his nose.
He LOVES this game! And it has taught him not to do anything without our permission. It has really helped with "stay" commands.
Now if I could just teach him to poop outside 100% of the time.....