Fear Aggression in 16 week old mini schnauzer?

Question
Hi Karen,

Our mini arrived fearful when he joined our family at 9 weeks but had made great progress.  Very little barking at new situations, a little growling when he wants to play with other puppies, still backs away from strangers but warms up quickly, until today.  

A friend came home with me at lunch time to see the little guy I've been bragging about so much and he was terribly aggressive.  Barking, growling, hair on his back standing up. He wouldn't even take the treats she offered him.  

Not sure if this is fear aggression or he's trying to protect me and/or the house as this is a stranger to him.  
If it is fear agression, what is the best way to nip it before it becomes a way of life for him.  NO and the dreaded penny can are how I handled it.  

Answer
Without seeing the situation, it is hard to say what set him off more than normal. Some are affected by louder or deeper voices, larger people, hats... any number of things that they might not have experienced before. Some people do not know how to approach dogs correctly, and tower/lean over them while coming down on them from above, and maybe staring them in the eye at the same time... all very dominant moves which can be pretty scarey! Your friend should have gotten down at his level (sitting on the floor would have been good), and coaxed him quietly to her while looking past his shoulder.

You need to get your puppy out to as many different places as you can... on-going obedience classes are a MUST. He needs to be hungry when you go, and have *EVERYONE* offer him a piece of his kibble (one person at a time, of course). After he takes the food (and you tell him what a GOOD boy he is [if he is behaving]), they should slowly pet him under his chin, coming at him from below with an open palm. He needs to be handled by a lot of different people so that he learns that strangers are *good* and that they will feed and pet him.

You don't say how old the puppy is now, but if my puppies do anything like that, I pick them up and scruff shake them while telling them to "KNOCK IT OFF!" as I stare them in the eye, and then I put them in the stranger's arms so that he/she can sweet-talk them, pet them, and maybe offer them a treat if I have anything handy (and I always have a pocketful if we are out and about). All things bad (and some good) come from me, and only good things come from strangers.

Karen