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FEAR AGGRESSION! The most common cause of aggressive behavior in dogs!

In around 90% of cases of aggressive dogs observed in my routine, fear is the main cause of the problem.

            A fearful dog tries to protect himself and tries to hide, run, and avoid contact with the source of his fear. But when he realizes that he has nowhere to go, defending himself is the logical next step. Showing teeth, growling, or even biting.

            And what happens after that? The target person moves back and walks away. There’s the reward: “IF I ATTACK THAT PERSON, THEY LEAVE ME ALONE, THEREFORE I WILL DO IT EVERY TIME”.

            This is a typical description of what we call “Learned Behavior”. I repeat what rewards me. If when I bite, that person walks away and leaves me alone, I will repeat that every time.

            There are many factors that can lead the dog to become fearful such as something that is sudden, invasive, or outside of normal dog interactions, or even an unfamiliar environment like a new house, or the veterinary clinic.

            So, what can I do? How can I not let my dog become fearful when facing the thousands of stimulators provided around the world? Noises, people, other dogs, or visitors in my house?

            The key word is SOCIALIZATION! Dogs are pack animals and need to be exposed to the world. But calm down there! I'm not asking you to take your nine-week-old puppy and throw him in the middle of a park with other dogs. This process must be gradual and respect the stages of the puppy's life.

            Separating puppies from litter under 8 weeks old should always be avoided.  There are exceptions, but they should be treated that way, as exceptions! If the puppy was born into a litter with multiple puppies, with a mother who takes care of him and nurses when nearby, then this puppy cannot be separated before two months of life.

            After that, comes the process of being taken into the new family, his first human family. Gradually, he will need to be exposed to the outside world, noises, visual stimuli, and other behavioral triggers.

            Look for places that offer daycare and socialization groups that separate puppies by age and behavior. That way, you can build social skills with other puppies that are the same age and in the same stage.



            If your dog is an adult and has been behaving aggressively for some time, there is a good chance he has already learned the behavior, having skipped through the early stages of reactivity, and going straight to aggression.

            That's because due to the many times he repeated the behavior, he learned that responding aggressively is the only way, so this has already become muscle memory; that is, he doesn't think, but just reacts.

            To resolve a situation like this, you will need time, patience, and repetition. For example, if your dog reacts aggressively toward someone riding a bicycle nearby, you will have to find a distance between your dog and a bicycle where the reaction does not yet exist. 100 meters? 200 meters? Across the street?

            When you put the dog in this situation, you will have to reward him a lot for being calm, even when he sees the bike in the distance. Gradually, day by day, week by week, you'll have to bring the bike closer to the dog and keep rewarding him so that he associates that bike is no longer a threat, on the contrary. Every time a bike approaches him, he receives a reward. This reward can be a treat, a toy, or attention from the owner.

            If you approach the bike too soon, the dog will likely go into an aggressive position again. It means you evolved too fast. Return to the original position and start over.

Marco Magiolo is a bestselling author, trainer, and speaker. Connect with Marco on social media and subscribe to future newsletters and updates.

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