My 4 month old female GSD becomes very nervous when playing tug. The hair on her neck stands and she becomes very defensive. I try to leave the tug with her and bring her into my arms. She would have non of it. All she wants is to get away and chew on the tug. I noticed that she's also begun to lose her teeth. Should I stop the tug games untill she's done teething? What should I be doing instead?

Any advise would be appreciated.

You don't have to stop tug work all together, but you might at this age want to lighten up a bit and don't tug on your end as hard, Keep the tug games short.
It sounds as though your pup may have bad nerves which is genetic. I can't say for sure because I don't know if the pup had a tramatic experience on the tug or not but if there isn't anything you can think of that probably made the pup yelp while on the tug my guess is he has bad genetics and the pup maybe better off as a pet, if your not sure what to look for in the pup I would find 1-2 clubs around and take your pup there, and ask for various opinions, don't take just one or two peoples evaluation as the likely. Schutzhund clubs are everywhere.

I appreciate the advise, but the thing that bothers me is that 2 weeks ago she was having a calm, full grip. I'm trying to know what might be the reason for her sudden change in attitude.
I also noticed that she's starting to lose interest in the tug. Maybe it's because I'm not letting her win lately and/or I'm overworking her. But that still doesn't explain her growling and snarling.

Regards,

You might want to invest in Ed's video drive focus and grip. Bernard shows how to calm the dog when he has his prey item in his mouth. The fact that the dogs hackles raise up and the pup growls to me is a serious factor which I associate to fear. Sometimes pups get crazy when they feel they will loose their prey. Try playing with the pup, and talk in a soothing voice. You should try and gently stroke the pup, saying good girl or boy as the pup is tugging. Also, don't fight with the the tug, just hold it and attempt to stroke soothingly the pups head. I'd do that every single time we play tug.

Yes... I got a bunch of DVDs already. I've began what you suggested. I'm not tugging anymore just holding the tug and soothing and petting her. She's back to her calm self. <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> . I guess I was just over doing the tug and made her fear losing the tug.

Thanks again.
Ps. I can't wait to get rid of her sharp baby teeth <img src="/ubbthreads/images/graemlins/tongue.gif" alt="" /> . I prefer duller adult teeth <img src="/ubbthreads/images/graemlins/tongue.gif" alt="" />

Thats great man! Also, I would just continue to sooth, and then gradually like in a month or so, start giving a very short fights with the tug like 2-3 seconds and then hold firmly and sooth and pet once again saying good girl, calm her before you let her win. and if she is still growling when you give her her short fights, then take the tug and raise it up until her front feet are on your thighs, waist or chest depending on how tall your dog is, but you want the back feet to still be on the ground, and give just enough tention that the pup won't pull the tug back down to the ground, at that point if you look down and she should be looking up, the two of you should be making eye contact and while she's in this position just sooth, praise and pet her for about 3-4 seconds and then let her win and let her run around with the prey item, use the leash and collar to hold her head up. With this be careful because of her teeth, but if you do it right it shouldn't be any different than tug when she has all fours on the ground, also, by the tug being up, you will notice her start to forge upward attempting to push her open mouth farther into the tug. I have found that with the tug in an up position like that they naturally feel more comfortable with the tug in the back of the mouth and therefore will continue to push their mouth upward in an attempt to get more of the tug in their mouth. This is one technique that the belgians use in NVBK to re-enforce full mouth bites in pups.