Smaller, older and male dogs are more likely to be aggressive and growl, snap and bark at humans, a study shows.
Some breeds are also more likely than others to exhibit aggressive behavior with long-haired collies, such as Lassie, the most aggressive of all breeds.
In contrast, Labradors and Golden Retrievers, loved for their cool temperament and gentle nature, were found by scientists to be the least aggressive breeds.
When comparing the Rough Collie (left) with the Labrador (right), the researchers found that the former is 5.44 times more likely to be aggressive.
Which dog breeds are the most aggressive?
The list below was compiled by researchers from Helsinki who studied the behavior of more than 9,000 dogs.
However, it includes only 23 breeds and is not exhaustive.
For example, notable breeds such as Rottweilers, Dobermans and British Bulldogs are not included.
- Rough Collie
- Miniature poodle
- Miniature Schnauzer
- German Shepherd
- Spanish Water Dog
- Chinese Crested
- German tip means
- Cotton Tulear
- Wheaten terrier
- Other things
- Pembroke Welsh Corgi
- Cairn Terrier
- Border Collie
- Finnish Lapphund
- Smooth collie
- Jack Russell Terrier
- Staffordshire Bull Terrier
- Shetland Sheepdog
- Lapponian Herder
- Golden Retriever
- Labrador Retriever
A study of more than 9,000 pets covering 24 breeds was conducted by researchers at the University of Helsinki.
It revealed the aspects of a dog’s personality that affect the likelihood of exhibiting aggressive behavior toward humans.
Small dogs were found to be more likely to behave aggressively than medium-sized and large dogs, but due to their size, they are often not seen as threatening, and the bad behavior is therefore not addressed.
The study, published in Scientific Reports, also found that canine dogs were more aggressive than females, and neutering them has no bearing.
How experienced the dog owner was also influencing the chance of aggressive behavior from a pet fish, researchers found, where the first dogs from inexperienced pet owners were more likely to behave aggressively.
The study also showed that dogs that spend time with other dogs behave less aggressively than those who live without other dogs in the household.
However, dog breeding is the factor that influences aggressive behavior more than any other variable, except in advanced age.
‘In our data set, the long-haired collie, poodle (toy, miniature and medium) and miniature schnauzer were the most aggressive breeds,’ says Professor Hannes Lohi from the University of Helsinki.
Previous studies have shown fear of long-haired collies, while the other two breeds have been shown to express aggressive behavior towards strangers.
‘As expected, the popular breeds of Labrador Retriever and Golden Retriever were in the other extremity.
‘People considering getting a dog should familiarize themselves with the breed’s background and needs.
‘As for breeders, they must also be aware of the nature of dam candidates, as both fear and aggressive behavior are inherited.’
Miniature Poodles (left) and Golden Retrievers (right) were considered the second most aggressive and second least aggressive breed, respectively.
Lapponic Shepherd dogs (right) are the third least likely dog breed to be aggressive, but Miniature Schnauzers (left) and the third most aggressive. Schnauzers are 3.34 times more likely to be aggressive than Lapponic shepherds
When comparing the Rough Collie with the Labrador, respectively, the least and most aggressive breeds, researchers found that the former is 5.44 times more likely to be aggressive.
‘In normal family dogs, aggressive behavior is often undesirable, while some dogs with official duties are expected to have the capacity for aggression,’ says doctoral researcher Salla Mikkola from the University of Helsinki.
‘At the same time, aggression can be caused by welfare problems, such as chronic pain.
‘Dogs’ fears had a strong connection to aggressive behavior, where feared dogs were many times more likely to behave aggressively.
In addition, older dogs were more likely to behave aggressively than younger ones.
‘One of the potential causes of this may be pain caused by an illness.
‘Impairment of the senses can help make it harder to notice people approaching, and dogs’ reaction to sudden situations can be aggressive.’
How old is your dog really in ‘human years’?
The often-stated statement that a dog year equals seven human years is false, according to a dog expert.
Instead, the equation is more nuanced and depends on the dog’s cognitive and behavioral traits over time as well as its breed.
A new study reveals that a dog becomes a teenager just six months old, is a full-fledged adult when it is two years old and is ‘senior’ around seven.
A review of previous studies of the dog’s age on pet health has been published in the journal Frontiers in Veterinary Science.
Dr Naomi Harvey, head of research at the Dogs Trust and academic at the University of Nottingham, completed the review.
She says just because dogs live seven times shorter than humans, does not mean that every walk around the sun is worth seven for a dog.
‘Dogs mature faster than we do,’ says Dr. Harvey.
‘Many hundreds of years old dogs have reached their full height, and most will have been through puberty or nearing the end of it, so they certainly do not correspond to a seven year old child!’
Instead of using the simplified factor in seven equations, Dr. Harvey to determine when a dog is a puppy, a young, an adult, a senior and a geriatric.
Her findings show that a one-year-old dog is a youngster who has just finished puberty and is related to a 15-year-old human.
But only 12 months later, two years old, dogs have reached full maturity in the same way as a 25-year-old person.
Dr. Harvey found that dogs can be considered entering their senior year at age seven and are considered geriatric at age 12.
Pictured how different measurements change a dog’s behavior over time. Green shows how the brain develops and then begins to decline in senior years; orange shows how some traits, such as cognitive decline, increase exponentially in a dog’s geriatric years; red indicates the slow decline in a dog’s activity and attention