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Dog Training


"If there are no dogs
in Heaven, then when
I die I want to go where they went."

Will Rogers


Dog aggression is a term used by dog owners and breeders to describe canine-to-canine antipathy.

Aggression itself is usually defined by canine behaviorists as "the intent to do harm". Many dogs will show "displays of aggression" such as barking, growling, or snapping in the air, which are considered distance-increasing actions, those which intend to get the person or dog to move away from the dog. Some dog-aggressive dogs display aggression that is mainly defensive, and they will actually harm another dog only if they perceive that they have no other option. Yet other dogs may develop dog-aggressive behaviour due to medical reasons, such as hormonal imbalances.

Dog aggression is a common dog behavior, and can be seen in all breeds of dogs, although some dog breeds have a predisposition to display such aggression. The breed standard usually spells out whether dog aggression is common in the breed and to what degree it is allowed. Most of the terrier breeds and the bull breeds have a higher likelihood of developing dog-aggression upon reaching maturity. Individual dogs may or may not display the level of aggression that their breed standard suggests.

As well as breeding, a dog's experiences may affect his chance of developing dog aggression. A dog that is attacked as a puppy may develop fear-based dog aggression towards all dogs, or perhaps only towards dogs that resemble the dog that attacked him.

It is important to note that dogs that display dog-aggressive behaviour do not necessarily show aggressive behaviour towards humans. The two types of aggression are not necessarily related, and do not always occur in the same animal

Factors contributing to aggression

Factors contributing to the likelihood of the development of dog aggression include:

Anxiety, fear or phobia
Lack of structure
Lack of proper exposure to other dogs during the critical socialization period
Early imprinting by an aggressive or nervous dam
A traumatic experience
Territorial behavior
Thyroid malfunction or other medical conditions
Abuse from previous owners
Medical or physical ailments
Breeding and genetic predisposition

Dog aggression manifests at the age of adolescence to social maturity (6 months to 4 years). Warning signs such as fear and/or nervousness around other dogs, displays of aggression only under certain circumstances (while on leash, in the presence of food, in the presence of the owner, etc.), or most commonly, over-the-top play behavior can be seen at any stage of the dog's development. Play behavior such as tackling, chasing, mouthing, nipping, pawing, and wrestling are all normal canine behaviors that serve the evolutionary function of preparing the young dog for later combat and hunting. Young dogs that engage in excessive amounts of these behaviors are much more likely to develop dog aggression as they age.

Dog-dog aggression should not be confused with dog-human aggression (also referred to as "dominance" aggression when directed at the owner).

Many people commonly mistake fear and anxiety-related aggression as "dominance aggression", which is inaccurate. Dominance is rarely the cause of aggressive behaviors in dogs, with fear and anxiety being the greatest cause of both dog and human directed aggression.

Lack of exercise is not a cause of aggressive behavior, although exercise boosts serotonin levels, which offset stress hormones such as cortisol, and can complement a behavior modification program. However, it is a common misbelief that aggressive dogs are "not exercised enough." Many aggressive dogs are exercised regularly.

Correcting dog aggression

The form that treatment for dog aggression takes depends on the underlying cause of the aggression, and an accurate diagnosis is therefore essential. Most reputable trainers will recommend that a dog has a vet check to screen for medical changes that may be the cause of the dog aggression before attempting any form of behavioural modification.

Dogs that are aggressive from fear can be that way either from genetic predisposition ("weak nerves"), or from a traumatic experience. With these dogs,


Behavior Problems:
- Barking
- Destructive Chewing
- Feces Eating in Dogs
- Food Guarding
- Jumping Up
- Mouthing and Nipping
- Object Guarding
- Problem Digging
- Urine Marking

Training Tips:
- Crate Training
- House Training
- Leash Training
- Sit Training
- Teaching Eye Contact
- Dog Communication
- Teaching Your Dog to Come
- Clicker Training
- Training Equipment

Keeping Your Dog Happy:
- Backyard Etiquette
- Breed-Based Activities
- Physical And Mental Stimulation
- Separation Anxiety

Getting Another Pet:
- Introducing A New Dog to Your Cat
- Getting Another Dog

For Puppy Parents:
- Preparing for A New Puppy
- Puppy Socialization

General Behavior:
- Canine Adolescence
- Dog Trainers & Behaviorists
- Pushy Dogs
- Dog Aggression
- Simple Solutions for Common Problems

a program of gradual desensitisation (DS) and counter-conditioning (CC) is often used in order to reduce the dog's reactivity to the stimulus that triggers the aggression. This can be accomplished through management (minimizing the dog's exposure to situations where he can practice the behavior while working on the training program) food rewards, toy/play rewards and praise as a reward. Ignoring aggressive behaviors is not standard or sound advice when implementing a DS/CC program.

Punishing aggressive behaviors through the use of leash "corrections" or leash "pops" and/or the use of training collars such as choke, prong or shock, is not recommended in cases of fear-based aggression, as these measures run a high risk of increasing the dog's anxiety in those situations. Further, it is difficult to control what the dog will associate the punishment to, as it is often what the dog is looking at the moment it is corrected, so sloppy application of punishment can create a more negative association to the stimulus than before. The final risk with punishment in treating aggression is that it runs the risk of punishing the aggressive display, such as growling, barking, baring teeth, etc., which are all warnings. Punishment decreases behavior, but does not modify it, so the dog may stop exhibiting aggressive displays (designed to increase distance between the dog and the stimulus) and skip straight to aggressive actions, such as biting.

"Dominance" based approaches (ie Cesar Millan), are highly controversial and more formal study is needed to validate this method. Further, these approaches carry a greater risk of behavioral fallout, such as the escalation of the aggressive behavior and/or redirected aggression on the owner or other family members.

United States

The United States has the highest reported incidence of dog aggression problems of any country in the world, with an estimated 4.5 million dog attack victims each year. One of the major contributing factors to the development of dog aggression is living as part of a multidog (more than one) household. More than a third of dogs in the United States—a higher percentage than any other country in the world—live as part of multidog households.

Another reason for this is that in America, a well developed country, people often shower their dogs with affection and toys; leading to the dog believing that it is dominant and the leader of the household. This could then lead to aggressive behavior.

Busy lifestyles are also a major contributing factor to the rising occurrences of aggression related attacks. As the American working week gets longer and longer, the responsibility of many dog owners often slips, leading to mild and more extreme cases of neglect. This neglect can start with something as simple as missing a walk here and there because of business meetings or late nights, neglect that does eventually have an effect on the mental and/or physical well-being of the dog.