A lot of people have misconceptions when it comes to which dog breeds are most aggressive and which ones aren’t. Aggressive dog breeds generally exhibit behavior that’s meant to scare or intimidate other animals or people. You can tell if a particular breed has aggression issues by the way it acts. You should especially pay attention when you are selecting a puppy. Is it the bully of the group, or quite shy and timid? Either case can lead to uncontrolled aggression, whether out of dominance or out of fear. Uncontrolled, regular growling, snarling, biting and lunging are dead giveaways that something’s up with the dog.
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From the Upcoming ueue, submitted by rappin.
What about kids with ADD? Other disorders that affect behaviour and interpersonal communication? Dogs can be born with a temperament that veers toward aggressive, no matter what you do. This is why many breeds are not only bred for their physical abilities, but for their manners.
As for the tendency of little dogs to be more aggressive, I think this is largely because, at least with breeds like dachshunds, their bites don't do enough damage for their poor temperaments to be isolated and bred out.
While I love pit bulls (never met a bad one yet) I know that just by virtue of their physical design they are incredibly dangerous. My biggest wish is that people stopped heaping all of their fears on the breed and focused on a more positive push to breed out aggressiveness, as was done with great danes.
And although I was attacked by a doberman in my youth, I still think they are majestic and beautiful dogs. I never learned to hate the breed because of one dog.
And I agree, that it's not always the owners fault for a dogs personality/temperament.
For instance, a mixed breed dog that my brother adopted from a shelter (that was given to my husband's aunt when it was about 7 months old). It was a male dog, looked like it had mostly Border Collie in it and that sucker was mean as hell towards other dogs. Nice as can be to people. Sweet and gentle, but even though it was fixed as a puppy, and no matter how socialized it got with other dogs, it still had that extremely violent dominant alpha dog thing going with the other dogs on the property and almost killed a few of them.
I remember when they first got the dog (it was only a few months old, still a small cute puppy), they also had another older puppy (that's now ours). And from the very start, the male dog would attack it.