Second dog doesn't get along
When someone tells me that they had gotten a second dog to keep the first one company but they don't get along so they need to get rid of the new dog, my usual reaction is "If you had 2 children and the second one picked on the first or was otherwise the dominant personality, would you get rid of the child?" Of course you wouldn't, you would teach both children the tools they need to adapt to the new situation. If possible you teach the older child to stand up for themselves and you teach the younger child to be respectful of the older child. You need to try to do the same thing with the dogs.
I'll also ask the ages of the dogs involved. Very often, a more mature dog will allow puppies (especially very young puppies) to climb all over them, bite them and generally be a royal nuisance. Up to a point. At some point the older dog will reach the point at which IT has had enough and put the puppy in its place. Sometimes this will be just a little grumble, sometimes a lifted lip, sometimes a rather vicious sounding growl followed by a snap, and sometimes even grabbing the puppy by it's neck/throat and pinning the dog.
Sometimes these interactions are going to sound like the two may be trying to kill each other. The puppy, especially if it's young is going to scream and yelp, the older dog may sound incredibly nasty.
So watch the dogs between these episodes. Do they get along otherwise? Are there certain triggers? particular toys or treats, food or water bowls?
The vast majority of the time, when you are dealing with an older dog/puppy situation things will settle down once they have established their pecking order. It may not be the one you would have chosen for them (sometimes the younger one will come out on top) but if they are comfortable with it, don't rock the boat. Sometimes when you are dealing with grown dogs things won't settle down and then you may need to consider rehoming the second dog, but give them time to work it out on their own, and this may take several weeks, occasionally longer, unless you truly are scared that there will be physical damage done to one of the dogs.
There are some things that you as the owner can do to help establish one of the dogs as the one having a higher pack position. The dog in the higher position gets fed first, is allowed out of the door first, gets prime sleeping spots. Pretty much, anything you intend to do with both dogs the more dominant one gets to go first.
But rest assured that you are not crazy, the dogs may sound like they are going to kill each other. They most likely aren't and things most often settle down after a few weeks or months.
Submitted by Marge (© 1998), and used with permission.
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