Dachshunds - the most aggressive breed of dog?

On a recent visit to the vet I had a long conversation about which breeds of dog vets are most wary of treating. Understandably the large fighting breeds such as the Akita, Sharpei and Chow Chow, featured highly. But what may surprise people is that included in this list were Border Collies, Jack Russell Terriers and Dachshunds. Many people are aware that Border Collies are often highly strung and quick to turn but many people might be surprised by the inclusion of JRs and Dachsies.

When selecting a breed of dog to buy many people focus on size rather than the background or origin of the breed. Jack Russells are one of the toughest terrier types to train as they are both strong willed and very energetic. They require firm, consistent discipline and since they are extremely intelligent they will continue to test their boundaries throughout their lives. With JRs if you give them an inch they'll really take a mile. 

As mentioned JRs are a very active breed and need lot of exercise and stimulation to prevent them becoming bored and destructive. Most behavioral problems are due to a lack of companionship, discipline, activity and exercise. If you've only seen perfect, well-behaved JR's, they are ones that were lucky enough to be exercised, well socialized, and trained. 

Aggression is often a problem with JRs and according to the Jack Russell Club of America, JRs are  particularly aggressive with other dogs of the same sex.

All these traits are typical to most terrier breeds but are particularly evident in breeds such as the JR which are still very much working dogs in much of the country

Dachshunds were originally bred to hunt badgers and other small prey. Opinion is still out on whether they should be considered a hound or whether their origin is closer to that of modern terriers. While their origins may still be in debate it is generally agreed that Dachshunds can be difficult little dogs.

Dachshunds boast an impressively loud and deep bark and without proper training can become nuisance barkers. While known for their devotion and loyalty to their owners many dachshunds will whine if left alone and are prone to separation anxiety. As a result of it is not uncommon for them to chew objects in the house to relieve stress. They rank 49th in Stanley Coren's Intelligence of Dogs, being of average working and obedience intelligence. However the dachshund is known for its houdini tendencies and is often able to break out of improperly made cage.

While these little dogs do not have a fearsome reputation (largely due to their small size and comical appearance) research has found that one in five dachshunds have bitten or tried to bite strangers, and a similar number have attacked other dogs; in addition one in 12 have snapped at their owners. This puts them at the top of the list of 33 breeds rated for their aggression, after academics analyzed the behavior of thousands of dogs.

Dr James Serpell, one of the researchers, said smaller breeds might be more genetically predisposed towards aggressive behaviour than larger dogs.

“Reported levels of aggression in some cases are concerning, with rates of bites or bite attempts rising as high as 20 per cent toward strangers and 30 per cent toward unfamiliar dogs,” he added.

Until now, research into canine aggression has almost exclusively involved analysis of dog bite statistics. But the researchers said these were potentially misleading as most bites were not reported. Big dogs might have acquired a reputation for being consistently more aggressive simply because their bites were more likely to require medical attention. 

The study conducted by researchers at the University of Pennsylvania’s Center for the Interaction of Animals and Society, is considered one of the most extensive of its kind and is the first to report replicated findings of breed differences in aggression, collected basic and behavior-related dog data from two separate groups.

The first group, consisting of members of 11 American Kennel Club recognized national breed clubs, such as The Labrador Retriever Club and The English Springer Spaniel Field Trial Association and the second involved an online survey both reached similar conclusions.

Dachshunds were one of the breeds that scored higher than average for aggression directed to both humans and dogs, putting them towards the top of the list.

Akitas, Pit Bull Terriers and Stafforshire Bull Terriers, breeds which have “bad boy” reputations, typically scored highly for dog-directed aggression - a result of their 'dog fighting' breed heritage. When they did injure humans, however, the injuries were understandably more severe than those inflicted by the smaller dogs.

Often the small size of dogs plays a part in the development of aggressive tendencies since small dogs are more likely to feel threatened by 'innocent'  human or canine interactions.

“Small size very likely plays a large role in the development of fear-based aggression among some breeds,” Duffy explained. 

“Smaller dogs may feel more threatened by other dogs and people — a perception that may be well founded.”

Other breeds with a greater tendency to bite humans included Jack Russell Terriers, Australian Cattle Dogs, Cocker Spaniels and Beagles.

On the “least aggressive” end of the spectrum were Basset Hounds, Golden Retrievers, Labradors, Siberian Huskies, Bernese Mountain Dogs, Brittany Spaniels, Greyhounds and Whippets.

Interestingly enough, several of these dogs also rated low for “watchdog behavior” and “territorial defense” behaviors, suggesting that they tend to be lovable family pets, but are less vigilant watchdogs than their smaller cousins such as Chihuahuas and Dachshunds. 

Much as in humans, behavioral patterns in dogs seem to result from a combination of environmental influences and genetics. 

Paul Jones, a Mars Veterinary genetics researcher at the Waltham Center for Pet Nutrition in the US, and his co-author identified locations in a dog’s DNA that contain genes believed to contribute to behavior, trainability and longevity, as well as body and skull shape, weight, fur color and length.

“By applying this research approach, we may be able to decipher how genes contribute to physical or behavioral traits that affect many breeds,” said Jones, who indicated future applications might include tailor-made foods and medicines, along with specific recommendations to individuals about what would be the “most lifestyle-appropriate pet for an owner.”

However Duffy countered that “just because there is a genetic component to behavior does not necessarily mean that it is predestined.”

“Anyone looking to bring a dog into their home should find out as much as possible about the individual dog’s history and temperament,” she advised. 

“Certainly some breeds are better with children than others on average. However, it wouldn’t make sense to pass up a well-socialized, well-trained, non-aggressive Rottweiler for an atypically aggressive Labrador Retriever.”.