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Author Of New Study On Canine Aggression Says Don't Blame The Breed, Educate The Owners

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Why do some dogs attack with kisses, while others... well, let's just get to the study, shall we?

Cutting to the chase: Dog breed is not a good predictor of aggression. This is according to a recent study out of the University of Bristol’s School of Veterinary Sciences, for which researchers surveyed U.K. dog owners to find out potential risk factors for dogs showing aggression toward humans in three contexts: With family members, and around strangers both inside and outside of the house.

The researchers of "Human directed aggression in domestic dogs (Canis familiaris): Occurrence in different contexts and risk factors," published in December in the journal Applied Animal Behaviour Science, surveyed over 14,000 dog owners in the U.K., collecting just under 4,000 responses.

About three percent of the responding dog owners reported aggression -- defined as "barking, lunging, growling or biting" -- toward family members. About seven percent reported aggression toward strangers coming into the house, and five percent reported aggression toward strangers out of the house.

Older dog owners (the humans being older, rather than the dogs) reported less aggression toward family members and toward strangers entering the house, while older dogs were more likely to be aggressive outside of the home. Spayed female dogs were less aggressive in all three categories.

Dogs purchased from breeders were less aggressive than those gotten from pet shops or rescue groups. Attending puppy class correlated with less aggression toward strangers both inside and outside the whole -- but attending a training class for four or more weeks was related to more aggression toward family members. (Remember: the researchers found correlations here, not causation, which means it's possible that dogs were going to obedience class for a long time because of their aggressive tendencies.)

"Ring-craft" classes, meantime, related to less aggression outside the home. Which leads to the very important question of what is a ring-craft class? It's the Britishism for dog show training. And here's a video of a dog named Pickles getting its first lesson, involving quite a lot of tail-wagging:

Most dogs in the study did not show aggression in more than one context. The researchers took this to mean that aggression is not an innate quality.

"It is important for dog owners and members of the public to be aware that any dog is capable of showing aggression, even where it has not done so in other situations," wrote the researchers in their report. "Equally, a dog which has shown aggression in one situation may not necessarily be ‘dangerous’ when in other contexts, an important factor in assessment of animals, for example in re-homing centres."

The study did find that some dog breeds were more likely to be reported as aggressive: hounds and dogs classified in the Kennel Club's "utility group" -- something of a catch-all category for dogs "having been selectively bred to perform a specific function not included in the sporting and working categories," according to the KC's website, and including miniature schnauzers, Boston terriers, poodles and Dalmatians. "Gundogs," as well as golden retrievers, terriers, setters and a host of other breeds had reduced aggression risks. None of the factors examined -- training, breed, age, etc. -- were dispositive, the study concluded, and "other factors specific to the characteristics and experience of individual dogs are likely to explain remaining variance."

Here's how lead researcher Rachel Casey put it in a blog post, straightforwardly titled "Dog aggression has little to do with breed, so test the owners":

So there are some breed effects on risk of aggression in some circumstances, but, importantly, the contribution these effects made was small. No more than 10% of the difference between aggressive and non-aggressive dogs were accounted for by the statistical models –- and these included all the significant factors, not just breed.

Clearly different breeds vary in aspects of their behaviour –- any dog owner will tell you that. But when it comes to risk of aggression, the influence of breed is pretty small. It’s also important to point out that we don’t know if these effects are related to the characteristics of the dogs themselves, because they could also be influenced by the type of people who choose to own particular breed types. So, in evaluating aggression risk for an individual dog, there are more important factors to consider than its breed.

Casey's blog post ends by cautioning against breed-specific legislation, laws that prohibit or otherwise regulate the owning of certain breeds of dogs. These laws are ineffective, Casey writes, and may even lead to an increase in injuries if the people drawn to the "cache" of owning a prohibited dog are likely to bring out that dog's aggressive tendencies.

"Policy should instead focus on the factors that influence the risk of aggression in the first place," she writes, proposing that public safety would best be served by driver's ed-like classes for dog owners.

"Every new driver is given a thorough education, which is bench-marked by a standard theoretical and practical driving test. We have well-established, and largely accepted, codes of practice that govern drivers' behaviour to reduce accident risk, and laws to enforce them," Casey suggests. "It would make sense to take the same approach for reducing aggression towards humans in dogs."

H/T: Smithsonian

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