Rough Collie Is Now The Most Aggressive Dog, According To Science

Often touted for being highly affectionate, Rough Collie has topped the list of 23 other types of dogs known to be “aggressive,” according to new study published in Scientific Reports.

Researchers from Helsinki who studied the behaviour of more than 9,000 dogs covering 24 breeds found that Long-Haired Collies, like Rough Collie, Miniature Poodle, and Miniature Schnauzer are more likely than others to exhibit aggressive behaviour.

The study also revealed that small dogs are more likely to behave aggressively than mid-sized and large dogs, but due to their size, are often not seen as threatening and the bad behaviour therefore goes unaddressed.

Male dogs are also more aggressive than females and neutering them has no impact.

The researchers noted that Labradors and Golden Retrievers known for their docile temperament and gentle nature, are the least aggressive dog breeds.

Notable breeds such as Rottweilers, Dobermans and British Bulldogs were however not included in the list.

Although breed impacts aggression, dog owners experience has a greater role in aggressivness, with the first dogs of novice pet owners being more likely to behave aggressively.

List Of Most Aggressive Dogs

1. Rough Collie 
2. Miniature Poodle 
3. Miniature Schnauzer 
4. German Shepherd 
5. Spanish Water Dog 
6. Lagotto 
7. Chinese Crested 
8. German Spitz Mittel 
9. Coton de Tulear 
10. Wheaten terrier
11. Pembroke Welsh Corgi 
12. Cairn Terrier 
13. Border Collie 
14. Finnish Lapphund 
15. Chihuahua 
16. Smooth Collie 
17. Jack Russell Terrier 
18. Staffordshire Bull Terrier 
19. Shetland Sheepdog 
20. Lapponian Herder 
21. Golden Retriever 
22. Labrador Retriever

Highly Socialized Dogs Are Less Aggressive 

The study has indicated that dogs who spend time in the company of other canines behave less aggressively than those that live without other dogs in the household.

Why Are Some Dogs More Aggressive Than Others?

The study has also shown that apart from advanced age, there is no other variable which influences aggressive behaviour in dogs than the breed. 

“In our dataset, 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 fearfulness in Long-Haired Collies, while the other two breeds have been found to express aggressive behaviour towards unfamiliar people.”

“As expected, the popular breeds of Labrador Retriever and Golden Retriever were at the other extreme.”

“People who are considering getting a dog should familiarise themselves with the background and needs of the breed.”

“As for breeders, they should also pay attention to the character of dam candidates, since both fearfulness and aggressive behaviour are inherited.”

Labrador Vs. Rough Collie

When comparing the Rough Collie with the Labrador, the most and least aggressive breeds, respectively, researchers found the former is 5.44 times more likely to be aggressive.

Causes of Aggression in Dogs

According to Salla Mikkola from the University of Helsinki, “In normal family dogs, aggressive behaviour is often unwanted, while some dogs with official duties are expected to have the capacity for aggressiveness”.

“At the same time, aggressiveness can be caused by welfare issues, such as chronic pain.”

“Dogs' fearfulness had a strong link to aggressive behaviour, with fearful dogs many times more likely to behave aggressively.”

“Moreover, older dogs were more likely to behave aggressively than younger ones.”

“One of the potential reasons behind this can be pain caused by a disease.”

“Impairment of the senses can contribute to making it more difficult to notice people approaching, and dogs' responses to sudden situations can be aggressive.”