Attacking puppies?

Not that I know of or have heard of.  Neither of mine have ever attacked a puppy of either sex.  My brindle, who likes to play with most dogs, will sort of ignore young puppies.  (Both my boys are intact.)

You said it all when you said "unsocialized."  I hope that this pup isn't too traumatized by this event.  If it happened during a "fear" period it might be imprinted for a very long time.

Xerxes, intact, won't attack puppies, but he does torment a huge Dane puppy, by barking at him.  The pup, who is about 3 times the size of X, submits whenever he hears X bark.  It doesn't matter where X is or what he's barking at.  But he's never attacked him. 

ORIGINAL: Xerxes

You said it all when you said "unsocialized."  I hope that this pup isn't too traumatized by this event.  If it happened during a "fear" period it might be imprinted for a very long time.

Xerxes, intact, won't attack puppies, but he does torment a huge Dane puppy, by barking at him.  The pup, who is about 3 times the size of X, submits whenever he hears X bark.  It doesn't matter where X is or what he's barking at.  But he's never attacked him. 

 
I was kind of concerned about this too.  Sally has met him on a couple of occasions, the latest one she tried to get him to play--play bowed, bounced a bit, etc.  The puppy didn't show her his belly, but he tucked his tail and generally submitted, but didn't want to play at all, he didn't even wag when he first sniffed her.  She didn't pester him at all though--as soon as she realized he was not interested she completely ignored him and went to playing with her beloved rubber horse feed tubs [].
 
I guess I'm just extra worried about this pup becoming fear aggressive towards dogs.  This girl has 3 kids and a horse and an unsupportive BF who really doesn't like dogs in the first place, and I just worry....

A number  of my experiences with Saints have been less than stellar.  Poor temperments are not uncommon in the BYB community.  Add that fact to the attack, this could be a major deal.  This puppy needs to be out with TRUSTWORTHY well socialized adult dogs. 

I get the impression this is a male dog as well.  The fights that could happen as this puppy ages and gets bigger and stronger could be really bad.  The GSD is a real liability.  Management of him needs to be examined carefully and improved (under fence access) etc. 

I know this may sound harsh, but it might be a good idea to rehome the puppy.

Yeah, this pup was definately from a BYB.  Luckily, the 2 dogs do not live at the same home, both attacks happened when they were visiting, and the pup is male.  I'm hoping she'll get him fixed, but who knows--I don't think she's decided yet.
 
I do also realize that the GSD is a liability.  I feel so sorry for him though.  He lives outside-he spends his days in a 6 by 8 ft pen with a bricked over floor, and spends him nights in a crate in the garage.  He is so starved for attention it's heartbreaking.  Whenever DH goes over there he goes in the pen and messes with him, and the dog just eats the attention up. 
 
All he has is a bowl of food, water, and a ball to play with.  They had a trainer take him and work with him, and the trainer told them what an intelligent dog he was and that he responded well to the training, but they didn't keep it up.  They keep saying that they want to bring him in the house, but he stinks (because he walks around in his own crap all day) and it's just too much trouble to give him a bath.
 
It's very, very sad....
 
 

it's probably predatory behavior. This unsocialized male probably thinks the pup is a small prey animal. And he's going to kill and eat it if he can.  

My Westie was attacked as a pup (at the "breeder's" house) by an adult intact dog.  The adult killed one pup in the litter and injured another severely (by biting both in the head) when they were 6-9 wks old.  Both pups were male, so maybe it was a predatory/survival of the fittest type thing.  But the adult male didn't have the best temperament to begin with so it shouldn't have surprised anyone (didn't surprise me).

In my personal experience, I've never had a dog injure or even threaten a young puppy like that.

In the Social Lives of Dogs Elizabeth Thomas Marshall describes how a female dog kills a puppy from the litter of another dog in the house. She says that in the pack mentality dogs can sometimes fear that there won't be enough resources to go around and feel a puppy represents a threat to them.

To counteract this experience, mrv is right - the puppy should have good social interactions with "trustworthy well-socialized adult dogs."  He didn't learn bite inhibition and other social things he would have had he stayed longer in the pack, so he needs to learn them from good, reliable, safe adult dogs. 
I wonder why someone thought bringing the puppy to the undersocialized outside dog was a good idea...