Breeds Prone to Aggression: The Hard Truth About Aggression and Why It Matters
Disclaimer: Every Dog Is an Individual
While this post explores common traits of dog breeds, it’s important to remember:
Not all dogs will act according to their breed standard.
Genetics play a significant role, but so do early socialization, environment, upbringing, training methods, and even individual temperament. A Labrador may not love swimming. A Border Collie might be mellow. A Shih Tzu might thrive with agility training.
Breed gives us a blueprint—not a guarantee.
As trainers, we look at the dog in front of us—temperament, drive, personality, and behavior—not just the breed label. Still, breed history provides critical context for understanding instincts, energy levels, and potential behavior challenges that are often misunderstood or mislabeled.
Knowing a dog’s genetic history isn’t about making excuses—it’s about training smarter, with more empathy and effectiveness.
Pit Bull Terrier
Fighting History:
Pit Bulls were originally bred for bull-baiting and, later, dog fighting, where they were trained to show strength and determination. These activities fueled the belief that Pit Bulls are inherently aggressive, but this behavior is not an excuse—it’s the result of intentional breeding and socialization practices.
Why they may be aggressive:
Pit Bulls are known for their strength, tenacity, and a natural instinct to assert themselves in confrontational situations. This breed can be more prone to dog-aggressive behaviors, especially if not properly socialized or controlled.
What owners need to know:
Aggression is not acceptable behavior, regardless of a dog’s history. Pit Bulls can be loving, loyal companions, but they require early, consistent training and socialization to prevent undesirable behaviors. Without the right guidance, they can develop a strong protective instinct that manifests as aggression, particularly toward other dogs.
Rottweiler
Fighting History:
Rottweilers were used for herding and guarding livestock and property. While they weren't bred specifically for fighting, their natural guarding instincts can sometimes translate into aggressive behavior, especially if they perceive a threat.
Why they may be aggressive:
Rottweilers are highly territorial and protective of their family. Their natural instinct is to guard, which can lead to aggression if they feel their home or loved ones are under threat. However, aggression is not something that should be excused—it’s a behavior that requires management.
What owners need to know:
Rottweilers are a powerful breed that requires experienced owners to provide firm leadership. Aggression should never be ignored, and without proper socialization and training, these dogs can become territorial and defensive.
Chow Chow
Fighting History:
Chow Chows have an ancient history in China, where they were used for hunting and guarding. While they were not bred specifically for fighting, their strong territorial instincts can lead to aggression if they feel threatened.
Why they may be aggressive:
Chow Chows are naturally independent and can be aloof and defensive around strangers. They are often described as "cat-like" in behavior, preferring to mind their own business and guard their space. However, aggression due to territorial behavior is not acceptable and must be addressed through training.
What owners need to know:
Chow Chows require strong leadership and consistent socialization. Aggression must never be excused due to their independent nature. Training should focus on ensuring that they remain calm in the presence of strangers and other animals.
Bullmastiff
Fighting History:
Bullmastiffs were bred to guard estates and protect property from poachers. While they weren’t specifically bred for fighting other dogs, their protective nature can sometimes result in aggression.
Why they may be aggressive:
Bullmastiffs have a strong instinct to guard their territory and protect their family. If not socialized or trained properly, this natural guarding behavior can turn into aggression, particularly toward strangers or other dogs.
What owners need to know:
Aggression in Bullmastiffs, as with any breed, should be addressed through training and socialization. Their size and strength mean that aggressive behavior is especially dangerous. Owners must take responsibility to ensure that these dogs are well-mannered and controlled in all situations.
Akita
Fighting History:
Akitas were originally bred in Japan for hunting large game, including bears, which required them to be strong and assertive. While not bred for dog fighting, their protective nature and assertiveness make them prone to aggressive behavior, particularly toward other dogs.
Why they may be aggressive:
Akitas are fiercely independent and protective of their family. Without proper training, they can become aggressive toward unfamiliar dogs or people. Their strong prey drive also means they can be territorial, leading to aggression if not managed properly.
What owners need to know:
Aggression in Akitas should never be excused. These dogs require a firm, consistent hand when it comes to training and socialization. Aggressive tendencies must be addressed from an early age to prevent dangerous behaviors.
German Shepherd
Fighting History:
German Shepherds were bred for herding and protection, primarily for police and military work. While not bred specifically for fighting, their role in security and guarding has led to a strong protective instinct that can translate into aggression if not properly managed.
Why they may be aggressive:
German Shepherds are naturally protective and territorial. Without proper training, their instincts to guard can lead to aggressive behavior, especially toward strangers or other animals.
What owners need to know:
German Shepherds are highly trainable, but they require an experienced owner who understands the need for structure and discipline. Aggression in this breed can often be traced back to poor management, so it is important to take immediate action if any aggressive behavior is displayed.
American Bulldog
Fighting History:
American Bulldogs were originally used for bull-baiting and to catch large animals. Their history as working dogs means they have a strong prey drive and territorial instincts that can sometimes translate into aggression.
Why they may be aggressive:
American Bulldogs are naturally protective and territorial. If not well-socialized, they can become aggressive toward other animals or people they see as a threat.
What owners need to know:
Aggression in American Bulldogs must be managed through early training and socialization. This breed requires an experienced owner who can provide consistent leadership to prevent aggressive behavior from developing.
Dogo Argentino
Fighting History:
The Dogo Argentino was originally bred in Argentina for big-game hunting, including wild boars and mountain lions. Its strength, courage, and ability to work in a pack made it an excellent choice for hunting, but it also has a history that ties it to aggressive tendencies due to its role in subduing large, dangerous animals. In some regions, it has been misused in dog fighting.
Why they may be aggressive:
The Dogo Argentino is naturally protective and can be territorial. They are also extremely strong and determined, and their hunting background means they have a high prey drive. If they are not properly socialized and trained, they can become aggressive, particularly toward other dogs or animals.
What owners need to know:
Dogo Argentinos require a confident, experienced owner who can provide strict training and early socialization. They are loyal and protective dogs, but these traits must be directed properly through structured leadership. Aggression toward other dogs, if not addressed, can be a problem.
Belgian Malinois
Fighting History:
The Belgian Malinois was originally bred for herding and protection work in Belgium. Known for their intelligence, agility, and strong work ethic, they are often employed in high-stakes roles such as police, military, and search-and-rescue work. Their history as working dogs means they are driven, highly energetic, and have a strong instinct to protect. While they are not inherently aggressive, their intense drive and focus can lead to behavioral issues if not managed correctly.
Why they may be aggressive:
Belgian Malinois are known for their strong-willed nature and dominant tendencies. Without proper training and an experienced handler, they may assert themselves as the top of the food chain, which can lead to aggressive behaviors and a lack of respect for boundaries. Inexperienced owners may struggle to establish themselves as the teacher, which can cause the dog to become more dominant, territorial, and potentially aggressive. When bred responsibly, Malinois should be balanced and resilient, able to stay calm and focused under pressure.
What owners need to know:
While Belgian Malinois are naturally protective and driven, aggression linked to poor breeding is often a result of their inability to handle stress. When bred responsibly, Malinois should be balanced and resilient, able to stay focused under pressure. However, it’s important to note that more driven, dominant Malinois can overpower inexperienced or inconsistent owners. These dogs have a strong will and can take advantage of a handler who lacks confidence or fails to establish clear bounderies. In such cases, the dog may begin to assume control of situations, leading to dominance-related aggression and behavioral issues.
Siberian Husky
Fighting History:
Siberian Huskies were originally bred by the Chukchi people of Siberia to pull sleds over long distances in harsh conditions. Known for their endurance, intelligence, and strong work ethic, Huskies were not bred for aggression. However, as a working breed, they were expected to be independent and self-sufficient in the sled-pulling environment. While they weren’t bred for fighting, their strong instincts and high energy can sometimes lead to behavioral issues if not properly managed.
Why they may be aggressive (due to poor breeding):
When Huskies are bred irresponsibly or without regard for temperament, they may inherit behavioral problems, including aggression. Poor breeding practices can lead to dogs with heightened territorial instincts, a lack of socialization, or even genetic predispositions to fear-based aggression. Huskies that come from poor breeding lines may also have a reduced ability to cope with stress or anxiety, making them more prone to aggressive behavior when they feel threatened or cornered.
What owners need to know:
Aggression in Huskies is often a result of poor breeding practices rather than the breed itself. When bred responsibly, Huskies are typically friendly, loyal companions. However, irresponsible breeders may prioritize physical traits over temperament, leading to dogs with behavioral issues. To reduce the risk of aggression, it’s essential to choose a reputable breeder who prioritizes socialization, health, and temperament in their breeding program. Early socialization, consistent training, and exposure to different people, animals, and environments are vital to preventing the development of fear-based or territorial aggression. Huskies require an experienced owner who can provide the structure and leadership they need to become well-adjusted pets.
Final Thoughts
Every dog breed was created with a purpose—whether it was herding, guarding, hunting, or companionship—and those original instincts still influence behavior today. When these ingrained drives are combined with poor breeding practices, the risk of behavioral instability increases dramatically. Breeders who ignore temperament and mental soundness can pass down traits like genetic anxiety, poor stress tolerance, or reactivity. This means that even breeds not typically labeled as "dangerous" can develop serious behavioral issues if their instincts aren’t properly understood or their genetics are compromised. While some breeds may cause more damage due to their size or drive, any dog can become dangerous in the wrong hands. Responsible breeding, purpose-aware ownership, and proper socialization are non-negotiable—regardless of breed.
Each year, approximately 4.5 million people in the United States are bitten by dogs. Of these, about 800,000 require medical treatment, and around 1,000 people seek emergency care every day due to serious injuries caused by dog bites.
Fatalities, while less common, still occur, with an estimated 30 to 50 deaths annually related to dog attacks. Between 2011 and 2021, the average number of deaths per year was around 43. Children under the age of 10 are especially vulnerable, making up a significant portion of both bite injuries and fatalities.
Although certain breeds like pit bulls are often involved in fatal attacks, it's important to remember that any dog, regardless of breed, has the potential to display aggressive behavior under certain circumstances.
Financially, the costs associated with dog bite injuries are significant. In 2023, homeowners insurance claims for dog bites reached over $1.1 billion, highlighting the frequency and severity of these incidents.
These statistics underscore the importance of responsible pet ownership, including proper training, socialization, and supervision, to minimize the risk of dog bites and ensure safety for everyone.