daschund and...

Some kind of small terrier like a Jack Russel or fox terrier?

ORIGINAL: ShaneandMiya
...He gets along with his 'pack' (the usual dogs at the park including mine) but goes crazy (in a bad way) when he sees any other dog.  That's probably due to his past though, not his breed, because they just got him two months ago and don't know anything about his past.

they were thinking maybe it was Jack Russell that he's mixed with because of the look of his face as well as his speed.  What do you think? 

 
Well, JRT would certainly explain the "goes crazy (in a bad way) when he sees any other dog".  I haven't met a JRT yet that hasn't been dog aggressive to some extent.  I'm sure there are some out there someplace who aren't, I just haven't met one yet! 

My guess is Min Pin.
They aren't always welcoming to unknown dogs, either.

I agree with Gina--Min Pin!

That is really funny that you should post this right now. We rescued 6 puppymill dogs on the 21....two of them min pins. However, I said that it looked almost like one of them was mixed with some daschund. He pretty much looked like a min pin, except for his snout. When I mentioned that to someone else, she said that when she walked into the room and saw the little guys face at the front of the vari kennel, she thought it was a daschund. When I saw your picture here, of your friends dog, the first thing I thought was min pin. 

Definately Miniature Pinscher! [] His description sounds alot like Penny. Very quick little dog who is not the most social thing.

ORIGINAL: micksmom
Well, JRT would certainly explain the "goes crazy (in a bad way) when he sees any other dog".  I haven't met a JRT yet that hasn't been dog aggressive to some extent.  I'm sure there are some out there someplace who aren't, I just haven't met one yet! 

My mentor (Russell breeder) has no dog aggressive dogs.  Neither of mine are at all.  Now, we wouldn't put two intact males together, but that goes for any breed.  It all depends on how careful the breeder is about not breeding dogs who are dog aggressive at all and socialization.  If we ever have one that is dog aggessive, it is spayed or neutered and very carefully placed in an appropriate pet home. 
 
My bet is on Min Pin. 

wow, I'd never even considered min-pin.  dh's grandma breeds min-pins so i should have made the connection.  now I'm almost sure that it's min-pin.
thanks for all the replies, it's helped a lot.
 
does anyone have any ideas on how to control his dog-aggressive behavior?  it's gotten to the point where if anyone new tries to come to the dog park, either they have to leave, or bruegger does because bruegger can't play without attacking.  and it's not like he's trying to kill the other dog i don't think, it looks more like just really really rough play.  brueggers owner actually got in a fist fight with a new dog owner who brought his puppy to the park (for one, the puppy was too young, two, it was a rottie which is a restricted breed at our complex which is where the park is, and three, the owner was forcing his dog to come in and she was terrified, shaking under her owners legs the whole time....then when bruegger got near her, he 'attacked', so the guys got in a fight over who should leave, etc)...it wasn't pretty. 
we love bruegger, and he gets along really well with the usual dogs there, we actually call him and miya a couple because they ignore the other dogs when they're playing.  but then again, all our dogs are their own little 'pack'.  bruegger's the only one that is against any other dogs invading their pack.  and it's really making everyone mad because we like bruegger playing with our dogs, but it's not fair for other dog owners who want to bring their dog down.
sorry i rambled.  but any kind of help would be great.  he's already got the dominant thing to an extent...he can just walk over to bruegger and if he has a certain 'tone' to his voice, bruegger flops over on his back immediately.  but when a new dog is there, he goes deaf and seems to have tunnel vision.