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Causes of Aggression in Dogs


There are different types of aggression in dogs and in order to properly assess aggression in dogs it is fundamental to resort to the help of professional for an in-person assessment. The reason behind this is the fact that each type of aggression may require a specific course of action in order to help the dog in the rehabilitation process. An owner attempting to deal with an aggressive dog may be a downright dangerous practice because with the wrong approach, the dog may become more and more aggressive.

What causes dogs to act aggressive and attack humans? Living with humans may trigger aggressive traits that must be taken care of in order to prevent the aggression from escalating. Following are some of the most common causes of aggression in dogs.

Pain Aggression

Sometimes when dogs attack owners, there's an underlying medical cause at play. Pain aggression is often the culprit when a previously mellow dog, starts attacking the owner out of the blue. Dogs who lash out when being touched may have an ear problem, or perhaps they have pain in their jaw. Sometimes, the source of pain is not readily identifiable. Certain medical conditions such as low thyroid levels can also cause dogs to become more reactive and this can lower their threshold for aggression.

It's always a good idea to see the vet to rule out pain or medical problems. Once medical problems are ruled out, then behavior modification can be started. This is very important because behavior modification won't work if there's an underlying medical problem at play.

Fear Aggression

One of the most common causes of aggression in dogs is fear. These dogs are really in a fight or flight mode, meaning they would like to escape from a situation rather than fight, however, when cornered, they may resort to aggression in order to protect themselves.

The body language of a dog in a flight mode is much more different from the body language of a dog in a fight mode. For instance, a fearful dog will often have its ears flattened back, its hackles up from the shoulder area to the tail, head lowered and the tail tucked behind the legs, an avoidance of direct eye contact and even urination when the fear is very intense. They may be growling and the growling intensifies as the person gets closer with teeth baring and signs suggesting an impending bite. Newly rescued dogs are often prone to becoming fear aggressive the first days with their new owners.

Fearful aggressive dogs should never be punished, helping these dogs out requires a systematic approach using force-free methods such as desensitization and counterconditioning. Fearful aggressive dogs need to learn to trust, and this often entails creating positive associations with the people they feel uncomfortable being around.

Possessive Aggression

Some dogs feel the need to guard objects, food and even people. Some dogs will attack anybody that will get too close to their owners. Some will be possessive of their food bowl and not allow anybody near them, even their owners. As in fearful aggressive dogs, these dogs simply lack trust.

Dogs that are food aggressive often benefit learning that when owners walk near their food bowl, not only will their food not be taken away, but food will be actually added. This should be done gradually until the dogs understands that good things happen by association when people are close by.

Maternal Aggression

Maternal aggression is seen in mother dogs who have recently whelped their puppies. It's not unusual to see mother dog growl and show her pearly whites to anybody who comes near her. After all, who can blame her? Born unable to see, hear and regulate their body temperatures, those newborn pups need all the protection they can have.

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The aggression in new mother dogs is the result of hormones and it tends to taper off as the surge of hormones decreases and the pups grow more independent.

Generally, it helps to not interfere as much as possible and let mother dogs have the peace and quiet she needs to accomplish her motherly duties. Refrain from the temptation of inviting over family and friends to see the new pups. If you need to weight the pups or clean up the area, it's a good idea to this when mother dog is out to potty or eat. After the first few days, you can toss mother dog a treat or two to eat (avoid hand feeding the treats as mother dog may misinterpret your hand movement towards her as an intent to touch her pups). Soon, mother dog will understand that that when you come close it's to give her treats and it's not your intent to steal her pups.

Dog Play "Aggression"

Sometimes, dogs may engage in behaviors that may seem like aggression when they are really not. Dogs who play rough may be perceived as attacking the owner. For instance, dogs who attack feet when walking may seem almost fierce, but all they are doing is treating those feet as prey to chase and bite. Just think about it for a moment, dog's don't go to attack street lamps or electric poles, for the simple fact that they are boring!

To reduce this type of rough play, it helps to become immobile and redirect the dog to play with a tug toy or flirt pole instead. You can also try to train your dog to do some attention heeling with some tasty treats. The goal is to get the dog's mind off the feet because there are more interesting things to interact with or more entertaining things to do.

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gwennies pen on August 21, 2009:

It seems a lot of the news lately speaks of these types of dogs. Perhaps it is certain breeds or just their environment, but this hub is very insightful!

Adrienne Farricelli (author) on August 21, 2009:

Some owners appear to be able to turn the dogs around by resorting to specific strategies (for instance I helped a food aggressive dog and now the owner can get close to him and he is doing great) however, it is highly recommended to consult with a behaviorist in my opinion because each type of aggression needs a specific type of approach and doing the wrong thing at the wrong time may be downright dangerous. For instance,, a dog that is fearful aggressive should never be punished or soothed, doing so would only exacerbate the aggression, a dog that is food aggressive should never be punished by taking away the food or petting him to calm him etc..All these types of aggression are caused by different motives and mostly behaviorists may be able to read the subtle body language as they are often not perceived by owners..For instance, in the case of the owner stating ''my dog bit me out of nowhere'' there are instead very subtle signs that are more likely not detected. Some however, may be a lost cause and these dogs are often ultimately and unfortunately, put to sleep. These are dogs that lead quite stressful lives that could not be rehabiitated.

ocbill from hopefully somewhere peaceful and nice on August 21, 2009:

how do you turn those dogs it a lost cause or only the Fido doc can help it. (Not sarcastic, being serious) I loved my dogs thank god they were not aggressive and in the south east US for that matter.

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