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Note: the image of the dog growling was not intended to label any particular breed as any breed can be aggressive. It’s just an image to support the topic of the blog post.
What's inside: No one wants to deal with a dog that bites. Trust me, I know. Learning the possible causes of dog aggression can help prevent future unwanted behaviors or even potential bites.
Sadly, I write a lot about dog aggression because it has impacted my life in unimaginable ways.
If I can save even one person from experiencing the agonizing thoughts that come with having a dog that bites that kept me awake many nights, tossing and turning, trying to figure out how I could save my dog from himself, it’s all worth it.
Having an aggressive dog is a tough journey but for me, it was a journey that not only made me love my handsome man dog even more which some folks might think is crazy but it also made me love dogs in general even more.
Aggression can be caused by several different things. These 7 different causes of dog aggression are not implied to be the only reasons for dog aggression.
7 Different Causes Of Dog Aggression
1. Lack of Proper Socialization
This is probably the most common cause of dog aggression. Puppies should always be properly socialized by the time they are 20 weeks old.
This could be challenging while you wait for your puppy to be fully immunized. One way to get around this is to have your friends with fully vaccinated dogs come to your house for play dates. This is a great way to socialize your puppy without exposure to public places and dog parks.
We found out after the fact that Frisbee was never socialized in his first 20 weeks. His litter was turned over to a shelter and when a rescue organization tried to pull him and his brother and sister, it was discovered that Frisbee and one sibling had Parvo. This led to being quarantined and more time with zero socialization.
I’ve always felt this was the cause of Frisbees’ fear aggression but only recently started feeling it’s not the only cause. I still believe it was a huge contributor but I am learning that some of my own behaviors with Frisbee may not have helped.
If you would like to read more about my journey with Frisbee and his fear aggression you can find his story by clicking here.
2. Being Isolated From Human Contact
Believe it or not, there are people who mistakenly believe isolating their dog from other human contact will be best for their dog and will create loyalty to the owner. This thinking is very wrong and can cause a dog to develop fear aggression.
We tried keeping Frisbee away from people to protect him and, of course, to protect someone from getting bit. In the end, we felt it was necessary for him to at least have a small, select group of people so he wouldn’t feel totally isolated.
We chose very carefully who we introduced Frisbee to and even when we felt he was comfortable with certain people (mostly family members and close friends) we always took it one day at a time.
Dogs have good days and bad days just like we do. Just because Frisbee was fine with my son-in-law one day didn’t mean he would be okay on another day.
We always went through a specific introduction/greeting and were careful to watch his body language for any signs of annoyance or discomfort.
The bottom line, we operated on the risk vs. reward system with Frisbee. What was the risk of leaving him out of his crate vs. the reward for him?
3. Excessive Physical Punishment
Excessive physical punishment is a no-brainer when it comes to causes of dog aggression.
People who are heavy-handed with corrections and hit their young pups are very likely to end up with a dog who is afraid of people and who actually may attack the owner as it gets older and is able to protect itself.
Okay, so let’s be real here. This is pretty obvious and a no-brainer to most people but unfortunately, it warrants mentioning.
And we aren’t saying you can’t punish or correct your dog but there is most definitely a right way and a wrong way to do it.
If you aren’t sure how to offer proper correction to your dog or puppy I highly suggest finding a good trainer or you can click here to get Brain Training For Dogs which will have plenty of resources to help you with training.
4. An Owner That Does Not Provide Proper Training
Not providing proper training for your dog is a common cause of dog aggression.
A new owner says we will train the dog later only to find that later never comes or later is actually too late. The dog ends up untrained and is now showing aggression.
Obedience training is very important and creates the master-dog relationship where the dog realizes the master is the alpha of the pack, not the dog. There are many different opinions about this topic of the human being the alpha so you have to decide for yourself what works in your situation.
Looking back I do feel that it was important for us to establish ourselves as leaders when it came to Frisbee. He was a highly reactive dog and he needed to trust us to take care of him so he could relax and just be a dog.
I never had a big dog so I believe unknowingly I was treating Frisbee like a little dog. I was babying him and just never established myself as the leader, as that person who would take care of things so Frisbee didn’t have to. Frisbee ended up a little confused and lacked confidence.
Let me add that dogs love their training sessions with their humans. This is a great opportunity for you and your dog to bond and connect on a whole different level.
If you want to help your dog live its best life and enjoy some one-on-one training with your dog, click here to check out Brain Training for Dogs. It’s packed full of all kinds of training for every situation and every stage of your dog’s life.
5. Anxiety Can Cause Unwanted Aggression
Anxiety can sometimes slip through the cracks as a cause of dog aggression but dogs, like humans, can feel anxious and anxiety can lead to aggression for your dog.
Anxiety can be caused by many things such as moving, adding a new human member to the home, losing a member of the household, or adding a new pet.
Other causes of anxiety could include your time away from home changing, people coming and going more often, physical discomfort or even your dog sensing something wrong with you.
It’s important to recognize any changes in your dogs’ behavior that resemble anxiety and then try to pinpoint the cause before it gets worse.
6. Chaining – Not Only Cruel But Can Lead to Aggression
While I would like to think that this doesn’t happen a lot, we all know it does and it’s also one of the causes of dog aggression. And, this one is actually against the law in many locations around the country. You can visit http://www.unchainyourdog.org/Laws.htm to see if your city or state is included.
If you see a dog inhumanely chained up, please report it to your local animal control.
Chaining is not only cruel but it will likely lead to aggression. I hate to say it, but I am going to say it…if you are chaining your dog, you shouldn’t have a dog.
7. Attack From Another Dog
Finally, if your dog was attacked by another dog it may not only have some fear when it comes to other dogs but this is also one of the causes of dog aggression.
If your dog is attacked, you may see him showing aggression when another dog gets too close. Your dog is simply trying to act nasty and tough so that other dogs will stay away.
This happened to Frisbee a couple of years ago while we were just sitting in a quiet corner of a park during a walk and training session.
Two dogs off-leash came running at him and they all got in a fight. I had Frisbee in a gentle leader harness and was yanking on him trying to pull him away.
Think “death grip”.
Not only did this not help because the other two dogs were loose and could keep coming at him but I also took away his ability to defend himself. I kept tightening the strap around his nose which left a mark for a very long time.
Luckily, no one and no dogs were hurt, other than the tongue lashing I gave the owners of the two unleashed dogs.
I always wondered what that situation did as far as taking Frisbee backward when we were working so hard with him to move forward.
Let me just say, if your dog isn’t perfect with the leave it or recall command, you should never have your dog off-leash in public.
If you want to learn how to teach this command, along with much other great training for your dog click here to check out Brain Training for Dogs.
Bonus Reason: Your Dog Might Be in Pain
Because I always like to over-deliver I wanted to share one more potential cause of dog aggression.
While there are many possible medical causes of dog aggression or even dog diseases that cause aggression it could be just as simple as your dog not feeling good or having undiagnosed pain such as arthritis for example.
You should definitely meet with your veterinarian if you suspect any sudden changes in your dog’s behavior, such as snarling or your dog bearing teeth, that might be a result of pain or illness. If you are asking yourself, why is my dog suddenly aggressive towards strangers, this could be the answer.
5 Types of Dog Aggression
Aggression in dogs can be a very serious problem that can create a tremendous amount of liability for you and your family. I know this first hand and I feel for anyone who has a dog with behavior or aggression issues.
Below are 5 different types of dog aggression that might help you identify why your dog is behaving aggressively.
Quite often this type of aggression is directed toward the owner. It can manifest itself when the owner tries to dominate the dog by making it do something that it doesn’t want to do.
Some examples would be commanding your dog to do something such as making him get off furniture or a bed. This is the type of aggression that happens where the dog feels he is the “Alpha” and doesn’t want to be “bossed around”.
I experienced this with Frisbee and I ended up learning his “hot spots” and how to handle him. For instance, if he was comfortable on the couch I wouldn’t lean over the back of the couch or startle him.
When he positioned himself comfortably on my bed but made it impossible for me to get comfortable I knew I couldn’t force him to move. I would call him off the bed which he obeyed willingly. Then I would get comfortable and call him back on the bed.
Watch for signs of dog aggression towards humans. Sometimes we need to respect our dogs’ moods and quirks and not force our will on them in every situation.
Common in the shy fearful dog and what we experienced with Frisbee.
The fearful dog is sometimes referred to as the most dangerous dog because you never know when fear will cause aggression to raise its ugly head making your dog very unpredictable.
Teach your children is to never try to approach a dog that appears fearful. Cornering a shy, fearful dog can be dangerous and you are setting that dog up to fail.
We have all seen this dog before. You know the one that is behind the fence and will not let you are anybody else through the gate. He is guarding his territory no matter where that is.
Territory aggression can happen in many situations such as on a piece of furniture, and any place in the house your dog feels belongs to him.
Dog on Dog Aggression:
This type of aggression you might see in your family dog especially if you had just one dog and add another. Check out our post with tips on introducing another dog into your home.
Dog-on-dog aggression could be caused by lack of socialization but also could just be jealousy, especially if this is happening between your own dogs.
Some dogs are just meant to be the only dog in a family and this could be for many different reasons.
If your dog shows signs of being uncomfortable dogs it’s best to respect him and not force him to interact with other dogs. Y
Food Aggression/Resource Guarding
Puppies and adult dogs can have food aggression issues for many reasons.
Signs of food aggression include your dog growling, snapping, and air biting if anyone comes near him while he’s eating. This can include another household pet approaching him while he eats.
If your dog is still a puppy, the best thing to do is teach your puppy early that he can trust that his food isn’t going to be taken away and you can touch it or move it or be near him while he eats and it’s okay.
If your adult dog shows signs of food aggression or resource guarding you can use the same techniques you would with a puppy to try to eliminate this bad behavior.
You can do this with treats and toys as well to avoid future resource guarding issues.
Wrapping It Up:
These are just some of the different types of aggression that you may see in your dog.
Socializing your pup before 20 weeks of age will help with some types of aggression and conditioning your dog to different situations will help with other types of aggression.
If you have an adult dog and it develops aggression be sure to seek the help of a trainer or behavior specialist that is qualified to help with the problem. Trying to resolve aggression on your own can be a long, tough journey and it’s best to hire a professional at the first sign of any dog aggression.
Frequently Asked Questions
Do Dogs Get More Aggressive as They Age?
Aggression in older dogs is not uncommon. Older dogs are likely to have some health concerns, such as arthritis, or vision or hearing loss. If your aging dog is uncomfortable or in pain this could most definitely lead to aggression which could be your dog’s way of communicating its pain to you.
Dementia or confusion can also trigger aggression. Some of these concerns can be helped with medical intervention, so it’s important to visit the vet as soon as possible.
Dogs can get aggressive due to illness, injury, or confusion, regardless of their age. As dog’s age, it’s common to have some health concerns. Something like dental pain, arthritis, or vision and hearing loss can trigger aggression in a senior dog.
As dogs age, their tolerance will drop so it’s helpful if you can provide your aging dog with peaceful surroundings
What Are Some Dog Diseases That Cause Aggression?
A variety of diseases or physical ailments can cause sudden aggressive behavior with your dog. Some of these include rabies, hormonal imbalances, hyperkinesis, neoplasia along with a variety of genetic disorders.
Also, any disease that affects the brain such as cancer can cause or predispose a dog to aggression.
If you suspect any type of illness or notice sudden and unusual behavior changes you should seek medical attention for your dog as soon as possible.
Why Is My Dog Suddenly Aggressive Towards My Other Dog?
There can be many reasons why dogs may start showing aggression to another dog in the home. A few of the most common reasons include frustration, resource guarding or pain, and/or illness. Sudden aggression can also be a result of one of your dogs’ aging.
It’s important to pinpoint the cause of your dogs’ sudden aggression in order to find the right solution to eliminate it.
What Causes Sudden Food Aggression In Dogs Towards Other Dogs?
Sudden trauma can trigger food aggression suddenly in dogs. Trauma can cause dogs to become more protective over their food resources.
Pain can also cause sudden food aggression. Pain causes stress which can lead to resource guarding.
Anxiety and fearfulness can also trigger food aggression, especially in dogs that are not typically dominant.
Dealing with aggression in dogs can be challenging and can wreak total havoc on your entire household.
If your dog is showing aggression you may have found the reason for that aggression right here in this article. Of course, there are more reasons for aggression so this is not the complete list.
If you want to see what we ended up doing with Frisbee that I feel had the best results click here to read: Starting A New Training With Frisbee I Never Thought I Would Do…
If your dog has suffered from any of these 7 causes of dog aggression be sure to contact a trainer or a canine behavior specialist to help you solve the problem as soon as possible.
When looking for a trainer or behavior specialist, do your homework, get references and make sure you choose a trainer with a history of success working with dogs like yours.
Living with an aggressive dog is not only challenging but can be a serious problem and of course, can create liability for you the dog owner. Be proactive and don’t ignore it. Treating aggression in dogs takes time and the longer you wait to deal with it the harder it will be.
If you’re on this journey with your dog my heart goes out to you and your family and of course, your beloved dog. Please try not to give up. There is help and equally important, there is hope. You can close the door on endless nights of tossing and turning for good.
I hope you got value from this post. Please share it and leave a comment below. If you have any questions or a story to share about your own experience with dog aggression, we’d love to hear from you.
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