You may have recently seen a dog show aggression by growling or even trying to bite. And, what lead you here might be the frustrating fact that it was your dog displaying these nasty behaviors. Let's say you own a corgi pitbull mix, a blend of two stereotyped aggressive dogs. You might immediately conclude that it must be because of the breed. But the truth is, it has little to do with the breed of the dog because any dog can become aggressive. It brings us back to the question, "What's causing their aggression?"
But, don’t fret. When dealing with dog aggression, one of the best things you can do is quickly identify the cause of aggression. Knowing the source of aggression will help you find the best options for correcting their behavior. So now, let’s take a look at some common causes of aggression in dogs.
EIGHT COMMON CAUSES OF AGGRESSION IN DOGS

8 – Illness
Some illnesses cause dogs to become aggressive. If your dog loves to horse around with their furry friends, but recently has become quick-tempered and lashes out, they may be suffering from a serious medical ailment.

7 – Frustration
Often called redirected aggression, this is frustration that stems from a dog not being able to get to something. The dog then takes out their frustration in other ways – usually at the expense of another pet or even human.

6 – Protective
We aren’t talking about the desirable protective behaviors we all hope our dogs display for our families and homes. Instead, the very dangerous behaviors that result when dogs become hyper-vigilant over their perceived territory.

5 – Leash Aggression
Is your dog is friendly and approachable most of the time? Does your dog start barking, lunging, or snapping at everything in sight as soon as you put on their leash? If so, your dog is leash-aggressive. Leash aggression is usually directed at other dogs and is known to stem from your dog feeling too restrained by their leash.

4 – Social Aggression
When multiple dogs coexist, they will work to establish a hierarchy for the pack. This rank and file system allows the pack to establish an order to things like who gets the coziest napping spot or is the first to eat. However, in times where a lower pack member disturbs the order, the Alpha dog might correct them with a display of aggression in the form of a growl or snap.

3 – Anxiety
Recent changes in a dog’s environment might be making them anxious, causing them to exhibit aggressive behaviors. Anxiety might be caused by the arrival of a new family member or moving to a new home.

2 – Resource Guarding
Dogs exhibiting resource guarding are aggressively possessive of the things they most cherish – like their favorite toy, treat, or even human. Dogs that are resource aggressive may lunge and at times snap at other dogs for getting too close to their bed, favorite chew toy, or dog mom/dad. If your dog shows these signs, please consult your vet as left unchecked, resource aggression can escalate to severe physical attacks.

1 – Fear
Fear is the most common reason for dogs to behave aggressively toward other dogs. Fear-based behavior often occurs through a lack of proper socialization, past negative experiences with other dogs, or abuse at the hands of previous owners. Usually, a dog will only exhibit aggressive fear-based behavior if they feel in danger and need to defend themselves.
I hope you’ve found this look at the top causes of aggression in dogs helpful and informative. Please remember that having an aggressive dog is challenging, and working with them to resolve their fears can be a difficult task. There is hope for aggressive dogs, and you shouldn’t just easily discard them because you’re afraid to put in the effort required to give them a safe and loving life.