Puppy attacked by older dog

Question
I have a 12 week old labrador puppy who is very outgoing, confident, and enjoys meeting other dogs. She has been cautious of big dogs, but has never been fearful. I walk her multiple times a day and often introduce her to dogs and people. So far she has been great - very gentle and outgoing. Today when I was walking her a large dog ran up to her. He was barking and growling and grabbed her by the neck. The dog threw her down and seemed to be attacking her. This went on for about a minute before I was able to pull her away. The owner claimed he was "just putting her in her place".

Since this time she is very fearful of other dogs. I have continued to walk her multiple times a day and haven't held her back from meeting other dogs. However, she remains fearful. She will put her tail in between her legs and stand behind me. I am worried she will remain uncomfortable around dogs or become aggressive towards other dogs after this experience. Is there anything I should be doing to ensure this does not happen? I would NEVER want my dog to act this way towards another animal or human. Any advice would be greatly appreciated.

Answer
That owner should be put in "his place", there are laws in most jurisdictions regarding dogs off leash.  The dog's response to your puppy was unacceptable and an indication he has problems, but that's not your concern.  First, do not allow unleashed dogs to approach you, go in the opposite direction in a calm manner; if an unleashed dog pursues you, turn toward it, raise your upper and lower lips (in a manner that resembles a snarl) and growl "get out of here" in a low voice.  Dogs do not expect humans to present with this facial posture and will always have a startle reaction.  In this way, you can protect your puppy from further abuse.  Meanwhile, help her to be calmer by giving her a "job" when other dogs approach and expect people whose dogs are on leash to control THEIR dogs, at your request.  Teach your dog to "come along" (follow you) and "sit" anywhere and everywhere before allowing her to interact with another leashed dog and request other people do the same with their dogs.  Explain she is a puppy and has had a fearful episode, most dog owners will be glad to cooperate and if they don't, too bad, keep walking.

You can see this sort of training in action at the following site:
http://www.youtube.com/watch?v=9zQAgY-fk6A

I strongly suggest you find a positive reinforcement training venue with a puppy kindergarten, where interaction is age appropriate and supervised by a credentialed trainer.  These places also have various levels of obedience training but you MUST be certain they use clickers or positive reinforcement, NEVER choke collars, coercion, punishment, etc.  Observe a class before bringing your puppy, be certain it's under control and not a free for all.  If your puppy interacts in a controlled environment, and then learns to 'work' around other dogs, she will relax and so will you.

If you're unable to find such a place, follow the guidelines for training and socialization offered at Dr. Ian Dunbar's DogStarDaily video training textbook:
http://www.youtube.com/watch?v=Hv38ornzzuQ