Are Some Dogs Born Aggressive?

By Ashley Tyler

The the Center for Disease Control reports that there are approximately "4.5 million dog bites occur each year in the United States."

But why?

Are dogs like people where some of us just have less friendly personalities, or does it all have to do with the environment the pup was raised in?

There seems to be two trains of thought on this.

Nature

Belgian shepherd puppy biting and pulling leg against white background
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The first one is that certain dogs have inherently aggressive personalities. Some dogs are bred to be sheep headers, to become service animals, and some are bred to be aggressive. The Animal Humane Society confirmed this by stating that "some dogs are genetically predisposed to aggression. Dogs of any breed can be selectively bred for aggression intentionally or unintentionally."

And to take it one step further — even if the breed is not what makes them aggressive, the breed does matter when it comes to how much damage is inflicted. For example, if a Chihuahua and a Rottweiler are put in the same fear-inducing situation, they may both bite and become aggressive, but the Rottweiler is going to cause more serious consequences because it was bred to be a bigger, stronger dog.

Mean Dog
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There is also evidence to support the thought that aggression has to do with a chemical imbalance in the dog's brain, just like humans. Lyn Johnson, an animal behavior specialist from Cornell, examined dogs who exhibited unprovoked aggression and found that they all had "abnormally low amounts of serotonin metabolites in their urine and cerebral spinal fluid." This suggests that aggression is associated with abnormally low levels of serotonin in the brain, just like that of prison inmates.

Nurture

Girl in autumn park training her dog in obedience
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Others believe aggression has more to do with how the dog is trained and raised. According to a study in the Journal of Animal and Veterinary Advances, a whopping 40 percent of dominance aggression in dogs can be traced to the owner having failed to successfully administer basic obedience training.

The archaic concept of becoming the alpha pack leader and showing your dog who's boss, is old news. Science Daily surveyed 140 dog owners and found that "many confrontational training methods, whether staring down dogs, striking them or intimidating them with physical manipulation does little to correct improper behavior and can elicit aggressive responses." Two wrongs don't make a right and you can't fix aggressive behavior with more aggression.

Aggressive dog
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No matter which stance you take, it seems both sides can agree with the Association of Pet Counsellors when they explain that "any dog has the ability to use aggression" and that while some dogs may seem naturally aggressive "it is more accurate to say that they are born with inherited tendencies that might, if not controlled, make aggressive behavior more likely."

Even if you do fall in love with a pup that is considered to be from an aggressive lineage, all that means if that your pup just needs "more careful nurturing than others to ensure that they do not grow up to use aggression inappropriately."

If you love it, it will love you right back,.

Which Breeds Are The Most Aggressive?

dogfight
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When it comes to aggression in dogs, some people are quick to assume the bigger breeds like pit bulls, Rottweilers and dobermans are the worst offenders. But in reality, according to a study published in Applied Animal Behavior00114-7/abstract) the most aggressive dog was the dachshund, chihuahuas came in second and the Jack Russells brought home third.

The American Temperament Test Society also found that "American pit bull terriers were among the most tolerant breeds."

Happy Dog Portrait
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This data though, it only as good as what is reported. And is the main reason why breed specific legislation (BSL) is not the answer. Pit bulls undoubtedly get the short end of the stick when it comes to dog laws, but Rottweilers, chow chows, and even chihuahuas are occasionally included. According to an article published by the national dog bite victims' group, Dogsbite.org, since the 1980s "more than 900 cities have enacted breed specific legislation," most of which is directed at Pit Bulls.

Many organizations, from the Humane Society to the U.S. Department of Justice, agree that BSL does not work. One prime example is the 1984 pit bull ban in Denver, Colorado. Since the ban, Denver "has more people hospitalized for dog bites than anywhere else in Colorado."

The moral of the story — don't judge a dog by its breed.