Adult Dog Is Attacking My Puppy!


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Does your adult and older dog act aggressive towards your new puppy? Scary as it might be, if you panic, it will only get worse. It is important to remember that most attacks on puppies are without permanent injuries, but of course, this depends on each situation.

The most important thing you can do is make sure all your pets and your family members are safe and without fear or worry. When your young puppy suddenly is attacked or possibly even bitten by the older dog, it can cause a lot of friction.

When a dog we have known for a long time suddenly shows a side it has never shown before, it can be difficult to trust the dog after such an event. It can also cause a rift in family members, some siding with the new puppy and others with the older dog.

Can I Stop My Grown Dog From Acting Aggressive Toward My New Puppy?

Aside from the aspects mentioned above, it is just unpleasant and outright dangerous to have an aggressive dog around, so like any good pet owner, you probably want to learn what you can do to make your dogs best friends instead of enemies. There is some good and some bad news for these cases, however.


First, the good news, a majority of older dogs that show aggression towards young puppies or younger dogs being introduced into the household can learn to tolerate their new family members.

In many cases, the dogs might even form strong bonds and act more like siblings than you might have expected from the initial reactions.


Now, the bad news. It is not guaranteed that any dog can be persuaded not to attack any other dogs that it perceives negatively. So you might have to accept that giving up one of the dogs is the best choice, no matter how much you tried. In this case, you have to realise you are not at fault.

Another thing to consider is time. It might be possible to train even the fiercest dog to not attack young puppies, but if it would take years to do so, is it really fair to subject the puppy to such an aggressive upbringing?

Many owners who have a dog that can not let the puppy alone opt to try training for a few months. If that fails, then most people look for adoption or other solutions to end the pain and fear that the puppy is going through.

Why Is My Dog Aggressive Towards Other Dogs?

In the very beginning of the introduction between your old dog and your new puppy, it is possible that the older dog might bark or growl to show dominance or to relieve the anxiety and uncertainty it feels. Unfortunately, these thoughts can manifest itself into aggression, so it is not always because your older dog hates the younger dog that you see an attack coming.

If you are in tune with your older dog, you might already have a sense of what sort of psychological reason your dog might have for being aggressive. Of course, the puppy might also carry a smell that your older dog is suspicious about, but in a few days time, when the puppy carries your scent and the scent of your home, it might not be an issue at all.

On the other hand, if your older dog attacks with bites or claws, things are a bit different. If the attack has caused wounds on the young puppy, first of all, you should call your vet to check that the wounds are clean or treat them with antibiotics to prevent infection and diseases.

Then once that is taken care of, and you have separated the dogs, so no more aggression is going on, you can try some of the various things we have listed in the article below.

An older dog attacking a new puppy does not need to be dangerous. Not all adult dogs attack with menace. Some are play biting, resource guarding, or similar. By studying the older dog’s body language with the puppy nearby, you can see what happens when your puppy approaches.

Reasons Why Adult Dogs Might Attack Puppies

There can be many reasons why an older dog dislikes the new young puppy you brought home. By figuring out why our dog suddenly wants to attack the small pup, we can potentially solve the issue by fixing the problems.

By removing the cause of the problem, your dog should feel more comfortable and happy. Of course, sometimes, it might not solve all of the problems, but at least it makes many dogs more susceptible to training and commands.

Behavioral Issues

First of all, owners should ask themselves how their older dog treats other dogs it meets on walks, in parks, or at friends and family. If the issue is only with your new puppy, then it might signal that a specific issue is the cause, whereas if your dog dislikes other dogs as well, it might be more of a behavioral issue.

Health Issues

It could also have to do with health issues. If your old dog is nearing its golden years, the hearing, sight, smell, and mobility in your dog could be severely decreased. So much so that your dog might think the new puppy is a threat, for whatever reason.

Clash of Energies

It might also be a case of the puppy bringing too much energy, whereas the older dog is used to a calm and collected lifestyle.

It is perfectly normal for older dogs to help their owners in correcting the behavior of puppies. However, it should never lead to biting or drawing blood, and there should be a clear distinction between play and fight.

Introduction Went Wrong

Some trainers think the way we introduce new pets to the existing ones plays a big part. For example, if uncertainty or unwanted behavior is not addressed early on in the introduction, it might escalate and produce aggressive behavior.

Jealousy or Uncertainty

Other times it can be out of jealousy. For example, if the two dogs share the same food bowl, dog bed, or favorite spot on the couch, things might get out of hand as well.

Dogs love nothing better than food, sleep, and relaxing with their human companions. Your dog might lash out due to frustration or mistrust by having these things threatened.

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Different causes for aggression in dogs

Some dogs might be defending their perceived home territory, while others might be jealous or unsure about the new puppy. Other dogs might just want to act tough in the beginning stages to let the young pup know who is in charge. It can also help learn the different signs and body language to help clue you when an attack might occur.

There are many types of aggression when it comes to dogs, and not all are equally serious. Read through our list below and try to see if any particular reason jumps out at you. By figuring out where the problem comes from, you are already well on your way to solving the actual problem.

  • Territorial 

It’s a well-known fact that dogs are territorial in nature, at least to some extent. While many generations have gone by since dogs were once wolves, some species and types lean more towards being territorial than others.

  • Excited Energy

If your adult dog is used to a quiet life and a young puppy that runs around and disturbs the peaceful surroundings, that could be a reason for the old dog lashing out. Try to judge on a scale of 1-10 the energy level of both dogs.

  • Guardian Mentality

Perhaps your dog wishes to protect you, and it’s food or something else from this new puppy. If the aggression tends to happen in a certain area, it might be territorial but could also be because the dog guards an area or perhaps an item such as the food bowl.

  • Jealousy

Some people dispute that dogs can get jealous, while others are not doubting for one second. If you can’t find any other reason on this list that could have caused your dog to be aggressive, consider if it might be jealous or feel left out.

  • Fearful Dog

Fear can manifest itself in many ways and be caused by many things. Fear of the unknown and fear of safety are among the most common ones. If your old miniature dachshund is suddenly met with a “giant” golden retriever puppy that feels large and imposing, your dachshund might just lash out of fear.

  • Socially Unaware

Sometimes your dog might mean well but simply lack the social skill set to judge when enough is enough. For example, it might be considering the act of biting as playing and not realizing it could cause actual harm to the puppy.

  • Injury or Medical Reasons

Other times the cause for aggression might lie inside the dog’s body. A number of various conditions and diseases can cause pent-up energy to manifest itself as an attack on your beloved puppy. It could also be reproductive frustration.

In short, there are many different reasons why a dog might become aggressive and many types of aggression. The approach we can take to correct the behavior and ensure safety can differ depending on our special case, so always be open to new ideas, but be critical as well.

What to Do if Your Adult Dog Attacks Your Puppy

When your older dog is attacking a new dog, one dog will often be the instigator. It is not guaranteed that your senior dog will be the one starting things, even if you see the older dog attacking first. Dog owners should know that the fight often starts before the physical interaction takes place.

By introducing a new dog, it is important to create positive associations and introduce them slowly, perhaps via a baby gate or similar barriers to ease into the meeting. In addition, learning the signs of when aggression might be expected can be a good way to curb aggressive behavior before it turns into violence.

Separate the Animals From Each Other

Separate the animals, and ensure they are not wounded or bleeding. Once this has been confirmed, you can focus on creating space for both of your dogs where they won’t run into each other without your supervision. Just like with crate training, potty training, and food bowls, your new family member might need to learn the basic rules.

Keep Calm and Collected

Be careful not to yell, panic or punish as this will only worsen the situation and make it more difficult to handle future similar situations. Some adult dogs might even learn that they get sent to the bedroom every time they start an attack and stop attacking by themselves.

Create Separate Areas for the Dogs

As a pet owner, your first responsibility should be to ensure safety and comfort, so by creating separate areas for the dogs to live in, you at least eliminate the danger of an attack. This might mean keeping one of the dogs in your bedroom, yard, or elsewhere while setting up a temporary perimeter.

See How They React to Being Together Outside of Home

Sometimes older dogs feel safe and comfortable in their home, but less so in public spaces like parks or on the beach. If you feel it is not too dangerous, it can be worth bringing both your dogs to an outside place and seeing how they react to each other.

If the older dog is territorial of the couch or protective of the food bowl in the house, you might not see any aggression from the older dog when it is not at home.

If that is the case, it could be a good idea to let the two dogs interact and get to trust each other outside. Bringing them on walks and hikes, letting them explore the beach together, and other similar activities could possibly build a bond between them that transfers back to the house. You might just find that your old dog suddenly accepts the puppy after a trip like this.

Contact a Professional to Assess the Situation

After any serious event, you might be uncertain if you can trust your dog, and you might even question your own capabilities as a dog owner and pack leader. But, regardless of how you feel inside, remember that you need to be strong in order for the dogs to succeed in the end.

Therefore, finding outside help to deliver a piece of information you were unaware of or just to act as moral support can be a great way to ensure you stay in control of the situation. It will give you a boost of confidence, and it might very well fix the entire problem.

This help could be from a professional trainer, a veterinary behaviorist, or similar that help ensure your puppy and older dog have good impulse control.

Attend Weekly Training With Others

By bringing your adult dog to training with other dogs, you might learn new things about your pet that you didn’t know already. It will also strengthen the bond between humans and animals, and you will get a chance to talk with many other owners and professionals.

Consistent Training

By sticking to your guns and not giving up, you show the dogs that your way of life is the only way you will accept. If you keep giving in and letting your older dog attack the puppy, all the dogs will learn is that fighting is to be expected. It can be difficult to keep trying, no matter how far away progress might seem. But if it is worth doing, it is worth doing right. So keep at it!

How Long Should It Take for an Adult Dog to Get Used to a Puppy?

Experts say it could take anywhere from a few seconds to a month or even longer. The average rule of thumb puts it somewhere around a few weeks. In this time, your animals will slowly learn the different personalities of each other. Their smells will mingle and become normal, and the hierarchy and energy levels will have been established.

If you experience a longer than average time for this to happen, you might have a potential problem at hand. Consider talking with a skilled dog trainer or behavioral dog expert to find out what might be the issue. You can also read through our article to get an idea of the various reasons that commonly cause dogs to be tense around each other.

What Techniques Can I Try to Stop My Dog Attacking My Puppy?

If you are considering teaching your dog to be calm and friendly towards your puppy, you should first be certain that you can do so safely. There are various techniques and philosophies on training methods, and while we won’t tell you which to use, we can give a short summary of the more popular ones out there.

Clicker Training

This form of training is when the dog owner uses a so-called clicker, a small plastic or metal implement that makes a unique sound. Once your dog does a good job, you click the clicker and provide a reward such as a treat or a belly rub to your dog.

Over time the dog will learn to associate good behavior with that sound, making it easier for you to tell the dog when it is behaving well. In addition, many people who swear by this method appreciate the fact that you can be precise with the timing of the sound, ensuring an understanding between you and your dog. It can therefore be an effective way of teaching your dog good manners.

Intensive Exercise

Sometimes your dog might be aggressive because it is too excited and redirects its energy in a negative direction. This one is relatively easy to figure out, as you can safely bring your adult dog on a long walk, possibly a run on the beach, and try to drain the older dog. Then, when you bring it back home again, you can judge how the dog’s behavior is compared to normal when it smells or sees your puppy.

Use the Process of Elimination

As we’ve mentioned earlier in this article, it can be important to find out exactly what causes the aggression. Then, by trying various techniques, like rigorous exercise to exhaust the dog, you can eliminate or confirm some suspicions as to what causes the issue. Then, if you are smart about this, you can pinpoint where the underlying issue is coming from and then fix that problem.

Extreme Measures

If it looks as though things are out of control, you may have to muzzle your adult dog until he or she gets the idea that it is not okay to dominate the new puppy. A muzzle is not a punishment and does not have to be uncomfortable. Consider the Pawliss Adjustable Anti-Biting Dog Muzzle, available at It is available in various sizes and can help to bridge the gap between “I hate this new puppy” and “I guess he’s okay.”

When to See a Dog Behavior Professional About Aggressive Behavior

If, after ~30 days of both dogs living under the same roof, they still have issues with each other, you should consider contacting a professional to assess the situation. What exactly you choose to call depends on your location, options, and budget.

If nothing else, giving your regular vet a call to see what they recommend can be a solid first option. They might also know someone skilled at handling cases like yours.

In some cases, depending on the severity of the issues, it might be necessary to contact someone after just a few days or weeks, or if the tension is very mild, you could wait an extra month before getting in contact with someone.

Know Your Dog’s Limitations

Not all dogs are meant to be living together under the same roof. Regardless of how much training you might put into having your dogs cohabit, sometimes it just doesn’t work. But that does not mean you have failed as a pet owner.

It might just be the case that the best thing for your young puppy is to find another home where it can live safely and freely without causing issues with your older dog. After all, it is stressful for both dogs to live in fearful or aggressive states, so you need to do what it takes to solve that, even if it means separating them for good.

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