Dog aggression

Dog aggression can refer generally to all canine aggression or can be used as short-hand for what is more accurately termed dog-dog aggression or dog-dog reactivity.Dog aggression is a common dog behavior exhibited by all breeds of dogs under the right circumstances, although some breeds may, for a variety of reasons, have a higher incidence of aggression than others. Aggression is driven by a variety of physiological and environmental factors. It is expressed through threat displays, defense displays, and attack.

Many dogs show "displays of aggression" such as barking, growling, or snapping in the air, which are considered distance-increasing actions, those that 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 harm another dog only if they perceive that they have no option. Yet, other dogs may develop dog-aggressive behaviour due to medical reasons, such as hormonal imbalances.

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. Although people tend to bring these reactions out of dogs more often than dogs themselves, dogs only pay attention to what their owners allow.

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 individual dog.

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 (in the past, this was referred to as "dominance" aggression when directed at the owner, but is now simply called owner-directed aggression).

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.

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