My pup is now 6 months old and weighs 50 lbs. To date, she has not had a serious correction; the only corrections that she's had have been related to pack issues, which have mainly been related to her interaction w/ my 5 year old.
She is vastly improved in the mouthing department now that she's done with teething; she still mouths a bit, but my arms have been fairly wound-free for the past month or so.
So here's what's going on:
When I get home from work (about 3:15pm) I take her outside for some exercise, which for us has been playing fetch and tugging when she retrieves the object i've been throwing. We have an empty lot that's part of the property where we live (about an acre) and she's on a 20 ft lead out there. I can throw the dummy(I mostly use a soft plastic retrieving dummy on a rope) a good 70 feet or so and she will fairly reliably retrieve it; when she brings it back to me, we have a tug session. If the dummy comes out of her mouth I tell her 'wait' and throw it again. If she has a good grip on it I'll tell her 'drop it' and trade for a treat, which most of the time she'll do.
When we are done (when I've had enough) i'll hide the dummy (generally stuffed down the back of my pants...nice visual, eh?!)
and pick up her lead to take her back in the house, or wherever.
2 days ago, she came at me after our game was over and started nipping. This escalated into hard biting w/ teeth bared. I'd reach for her collar and she'd jump and twist and keep biting my arms. I finally got my foot on the lead and when she couldn't jump anymore she calmed down. I'm now sporting matching bruises running up and down both arms. (no skin broken)
Yesterday, we played fetch only (retrieve and throw, with no tugging) and at the end of our fetch game, she came at me again. I was quicker this time and got my foot on the lead before she nailed my arms. She kept biting my feet, and I just kept saying 'No, no' in a calm voice, and she stopped biting fairly quickly.
So, should I be correcting for the biting? I want to be able to control when the game is over, without getting nailed everytime.
My thoughts are that once her prey drive kicks in, she doesn't want to quit and is frustrated when the game ends.
I have a bit more to watch of 'pack structure with the family pet' and I am making some adjustments based on what Ed says in that video. Nothing huge, but some small things that I think will help...
Sorry for length of this post...

I'll take her.

Hehehe. It sounds like Puppy play to me. I've learned a lot about that recently thanks to Mike Schoonbrood and others on this board. She's feeling her oats, just like a teenage boy wanting to wrestle with his dad, it's a game that builds her confidence.

What you do with it depends on your dog, and on what you want. If you're doing Schutzhund and your dog isn't overly dominant you may want to encourage this type of play. Establish boundaries, but do some roughhousing. It will build the dogs confidence and dominance, which are closely linked.

If you're not doing a biting sport, and your dog is already confident enough, there's no reason to encourage it. Bring some high value treats and start working OB at the end of your fetch sessions. When the dog comes in throw it a treat for the last retreive (and to let it know that you have yummies) and go right into fast paced obedience. Slow down the pace of the obedience over time, then when the dog is calmly in a down, approach for the leash.

Don't flail your arms around, don't reach for the dog or lean towards it/over it, just be a tree that does Obedience. Be a tree.

David, thanks for the response. I will remember to keep my treat bag w/ me from now on and go right into obedience at the end of a play session.
I don't really want to encourage her to bite any more than she already does.

 Quote: David Eagle

Bring some high value treats and start working OB at the end of your fetch sessions. When the dog comes in throw it a treat for the last retreive (and to let it know that you have yummies) and go right into fast paced obedience. Slow down the pace of the obedience over time, then when the dog is calmly in a down, approach for the leash.

Don't flail your arms around, don't reach for the dog or lean towards it/over it, just be a tree that does Obedience. Be a tree.

David, this has worked very well with her, and I notice that when we're finished playing and move right into obedience her response time is very fast.
You saw from my other post that I want to cut down on the tugging, so we're sticking with fetch for awhile. Thanks!