Needle Teeth
Puppies are very oral. They don't have hands, so they can't pick things up and examine them the way a small child would. Instead, puppies use their mouths to taste, feel, and carry things. Because of the way puppies explore their worlds, a common issue for the shepherd puppy owner is that her puppy is biting. Even if the bites aren't too hard, those little needle teeth can really hurt!
When your puppy was with his mother and littermates, if he bit another puppy too hard, that littermate would scream and refuse to play with him. If your puppy chomped down too hard on his mom, he got a swift but controlled correction that likely made him shriek — not out of pain but as a terrified apology). Your puppy and his littermates were all learning “bite inhibition,” or the ability to control biting, whether in play or as a defensive reaction.
Now your puppy no longer has his mother and littermates to help him continue learning, and it will be at least six to eight weeks before you can enroll him in a puppy class where he can continue to learn this necessary skill. In the meantime, you are in charge of this vital training.
You have to let your puppy know that hard bites are unacceptable but that controlled mouthing is okay. When your puppy bites too hard, yelp loudly, turn your back on him, and ignore him. If he's not going to play nicely, you're not going to play at all. After several minutes, you can go back to playing with your pup, praising him calmly if he's mouthing gently. It shouldn't be long before your puppy catches on that hard biting is not allowed.
Does your puppy tend to nip the most when you first walk in the front door? When you leave, place a chew toy by the front door that you can carry in with you. Before your puppy has a chance to greet you at the door with teeth, give him the toy. He can't nip you if he's got something in his mouth.
Another form of biting that a shepherd might exhibit, particularly if he's from lines with strong herding instincts, is nipping at or gripping people's heels. Running children are prime targets for this kind of behavior; however, some dogs will nip adults, too. Here are a few tips to help make this herding instinct more manageable:
Don't permit people to run inside the house.
Yelp if you are nipped and ignore the puppy.
Praise your puppy when he follows you without nipping at your heels.
Don't let anyone laugh when the puppy nips. He will take this as a reward for his behavior.

