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Can an Aggressive Dog Be Rehabilitated After Biting?

Can an Aggressive Dog Be Successfully Rehabilitated?

Can an Aggressive Dog Be Successfully Rehabilitated?

Agressive Dog Rehabilitation

Can an aggressive dog be rehabilitated after biting? This is a good question that many dog owners may ask. The truth is that there are several variables that can make a great difference in a dog's aggression "prognosis."

A Note About Realistic Outcomes

Before we begin, however, it's important to mention that you should never trust a professional who offers guarantees about your dog's aggression being "cured" or fixed "once and for all." All cases are different and some dogs may respond well to behavior modification, others may require strict management, some may need to be rehomed (only if safely and responsibly), and in worst-case scenarios, some may even need to be euthanized, sadly.

While there may be several different outcomes, no dog should ever be considered hopeless until it has at least been given a chance and numerous efforts. Don't let anybody pressure you and tell you what to do—major decisions regarding your dog's welfare are ultimately up to you. Sometimes all it takes is just finding the right professional to see marked improvements in your dog.

Understanding Canine Rehabilitation

In this article, we will be taking a look at some variables that can make a difference in the outcome of behavior modification for aggressive dogs with a bite history. Here is a brief list of some of the topics that we will address.

  • Why many "philosophies" and adherence to temperament tests have weak track records and fail to provide much reliability and validity.
  • Scientific ways to assess behaviors based on more objective, quantifiable strategies.
  • How a behavior history may provide better insight into how likely a dog may be rehabilitated.
  • The importance of ruling out potential causes of medically-induced aggression.
  • Bite inhibition and its fundamental role in preventing dogs from becoming ticking time bombs with enormous liabilities.
  • A summary of Ian Dunbar's dog bite scale.
  • An explanation of bite threshold and one big mistake many dog owners make when their dogs growl.
  • The importance of finding the right professionals to prevent the aggression from getting worse.
  • The big role dog-owner compliance plays in potential success.
Not all behavior evaluations tell the whole story.

Not all behavior evaluations tell the whole story.

Why Not All Behavior Evaluations Are Reliable

There may be several methods to evaluate aggressive behavior in dogs, but several of them may not have much validity. There are currently non-standardized parameters to rely on, and in many cases, "so-called professionals" in the field that make assessments based on their individual opinion and training philosophies, rather than taking a scientifically-based stance.

To make matters worse, there are still professionals who rely on certain tests that have weak track records and fail to provide much reliability and validity. Tests that come to mind are temperament tests, which may cause dogs to react differently than they would under "normal" circumstances and that just provide a "snapshot" of a dog's behavior in a specific context. With non-standardized parameters and testing methods with weak track records, how can it be possible to attain better insight into a dog's aggression prognosis and whether a dog is a good candidate for behavior modification?

Fortunately, there are more accurate methods that involve objective, quantifiable strategies such as taking a look at a dog's behavior history, ruling out medical problems, assessing a dog's bite inhibition and bite threshold, and considering the dog owner's level of compliance.

"The best predictor of future behavior is past behavior."

"The best predictor of future behavior is past behavior."

A Dog's Behavior History Offers Valuable Insight

Scientists who study human behavior and psychology appear to agree that past behavior is a useful predictor of future behavior, hence the saying: "The best predictor of future behavior is past behavior." By taking a look at a dog's behavior history, it is possible to gain insight into how likely it is that the dog may be rehabilitated successfully along with other strategies.

A functional analysis based on the dog owner's recollection of the events that triggered a bite may help reveal the evocative stimulus (antecedent) that triggered the behavior and the potential consequence that maintains the reactivity/biting behavior in the case of a repeat biter. While a dog's behavior history may be more accurate than testing systems that may fail to emulate real-life situations, there may be weaknesses in this approach as well.

For instance, dog owners may not be able to recall the exact events that triggered a behavior. Or they may assume that they know the trigger when the dog was actually responding to something else. For instance, a dog owner using a shock collar may assume that their dog bit them because another dog appeared at a distance at the time the redirection and bite happened, when in reality, the dog was simply startled by the shock collar and the bite was an impulsive reaction.

The more clear and consistent the stimuli that trigger the behavior are, the better the chances for behavior modification. Aggressive behavior that is context-specific, and therefore, triggered by predictable stimuli that can be managed, is much better than aggressive behavior that happens erratically without any clear identification of stimuli that evoke the behavior. These are much more complicated cases and may have a poorer prognosis due to the unpredictable nature of the aggression.

Aggression can be triggered by acute or chronic health issues in dogs.

Aggression can be triggered by acute or chronic health issues in dogs.

A Dog's Medical History Might Lead to a Solution

Sometimes, aggression in dogs may be induced by medical causes. For this reason, it's important to have an extensive veterinary exam before assuming the dog is suffering from a behavior problem. This plays a very important role in determining how likely an aggressive dog can be rehabilitated.

There are several medical conditions that have been known to trigger aggressive displays in dogs. For instance, hypothyroidism, a condition known to affect the dog's endocrine system that causes a low level of thyroid hormones is a known culprit for aggression. Affected dogs develop weight gain, hair loss, lethargy, low tolerance for cold, and behavior changes such as anxiety, fear, and aggression. While it's a bit unusual for dogs with hypothyroidism to develop aggression as a stand-alone symptom, running a thyroid test is still worthy.

Other possible conditions known to cause medically-induced aggression in dogs include acute or chronic pain, sensorial impairment (deafness, loss of vision), and neurological disorders such as seizures or certain brain conditions. If a vet determines that a dog's aggression is medically induced, there may be good chances that the aggression may regress once the underlying medical cause is managed and/or properly treated.

It's important to determine how hard the dog is biting.

It's important to determine how hard the dog is biting.

Observing the Level of Bite Inhibition

How much pressure is exerted by a dog's jaw when a dog bites plays a very important role in whether an aggressive dog can be rehabilitated successfully. Truth is, if a dog has bitten in the past and caused a great degree of damage, there is a greater concern for protecting the owner and the family. This places even more pressure on the professional helping to rehabilitate the dog, considering that it is difficult to ensure 100% reliability when implementing behavior modification.

How Do Dogs Attain Good Bite Inhibition?

Good bite inhibition is a result of nature and nurture (genes and the environment in which a dog is raised). Genetically, some dog breeds were selectively bred to have a soft mouth so that they do not put pressure on retrieved downed birds that were meant to be consumed on the table with the meat intact. However, even within these breeds, you can occasionally stumble upon a hard biter. Even within a litter of pups of the same breed, there may be dogs that bite softly and others that use excessive pressure. It's not yet clearly understood why, under a similar context, two dogs would bite using different pressure.

To a great extent, good bite inhibition is taught when the puppy is in the litter and interacting with the mom and siblings. Any rough-mouthing evokes a strong yelp and withdrawal from play in the littermates. Soon, this repeated feedback teaches rough pups to play more gently if they want to keep playing with their littermates.

Bite inhibition should then be further refined once the pup is in their new home and learns that humans have even more sensitive skin. Continued play with other puppies is still important at least until the puppy's permanent teeth have erupted. Generally, puppies should have attained a good level of bite inhibition by the time they are 5 to 6 months of age.

A dog with good bite inhibition, therefore, is more likely to have a good prognosis compared to a dog that has a history of exerting mutilating force with its jaws. In this case, the key factor is the pressure exerted with the jaws. Of course, a large breed dog compared to a toy breed dog is more likely to cause damage which also plays a role in the prognosis. Below is a summary of Ian Dunbar's bite scale.

A Summary of Ian Dunbar's Bite Scale

  • Level 1: No skin contact by teeth
  • Level 2: Skin contact but no puncture; skin nicks (less than 1/10th of an inch deep) and slight bleeding is possible
  • Level 3: 1–4 punctures from a single bite not deeper than 1/2 the length of the dog’s canine teeth with possible lacerations
  • Level 4: 1–4 punctures from a single bite with one puncture deeper than 1/2 the length of a dog’s canine teeth with possible deep bruising/lacerations
  • Level 5: Multiple bites with at least 1 to 2 level-4 bites
  • Level 6: Death
It's important to determine the dog's level of bite threshold.

It's important to determine the dog's level of bite threshold.

Level of Bite Threshold

All dogs (even the most mellow ones) have a bite threshold. Given the right circumstances, a dog will revert to biting once a certain level of stimulation has been surpassed. A bite threshold is, therefore, the quantity and level of intensity of triggers necessary to evoke a dog to bite.

Does the dog who resource guards charge anybody who enters the kitchen or just when people attempt to grab their food bowl? Does the dog with a history of biting children charge when the children are playing nearby or when he or she is cornered with no escape route? Dogs with a low bite threshold are dogs that are more likely to bite with little provocation, and therefore, are deemed more dangerous, especially if the low bite threshold is accompanied by poor bite inhibition.

On top of this, worthy of consideration is whether the dog emits any warning signals before biting. A big mistake many dog owners inadvertently make is punishing dogs for growling or air snapping. This potentially leads to dogs that bite without warning, which makes them more of a liability. We want dogs to growl because that's their warning system that may help prevent a potential bite.

Finding the right professional for the job is the most important factor in rehabilitating a dog.

Finding the right professional for the job is the most important factor in rehabilitating a dog.

Using the Right Professionals 

Behavior modification for dog aggression requires a high level of expertise. The ideal professionals are those that focus on the observable, quantifiable behaviors emitted by the dog rather than applying labels and adjectives as to why the dog behaves in the way it does. There are also considerable risks when outdated dog training philosophies with no foundation in science are utilized; these often include the use of confrontational or aversive methods.

A study published in the Journal of Applied Animal Behavior Science has demonstrated that confrontational training methods such as staring down dogs, striking them, or intimidating them with physical manipulation, have little effect in correcting improper behavior and can elicit aggressive responses.

Several completed surveys revealed that confrontational methods such as hitting or kicking a dog when performing an undesirable behavior, growling at the dog, alpha-rolling the dog, staring the dog down, or grabbing the dog by the jowls and shaking them evoked an aggressive response from at least 25% of the affected dogs.

It's important to work with professionals that are well-versed in using humane, force-free behavior modification.

This study highlights the risk of dominance-based training, which has been made popular by TV, books and punishment-based training advocates. These techniques are fear-eliciting and may lead to owner-directed aggression.

— Meghan E. Herron

Dog owners play an important role in successful rehabilitation.

Dog owners play an important role in successful rehabilitation.

Successful Rehabilitation Has to Do With Owner Comittment

Can an aggressive dog be rehabilitated after biting? To a good extent, the answer to this question also depends on the dog owner and his/her level of commitment in managing the dog's environment. It also depends on the owner's level of competence in carrying out the assigned exercises for behavior modification. It is often critical that family members participate as well.

An important role of behavior modification is management, which requires strict adherence to preventing the dog from rehearsing problematic behaviors. This is not easy and is the one aspect of behavior modification that dog owners most often struggle with. For instance, in a dog prone to resource guarding against people, successful management would entail feeding the dog away from people. In a dog prone to reacting aggressively towards children, the dog should be locked up when the neighboring kids come to visit.

Management may require a lifelong commitment to safety. Several behavior modification exercises often entail implementing some form of desensitization and counterconditioning which require skill, good timing, and correct execution. Many setbacks in aggressive dogs are due to incorrect implementation.

"Where there is a will, there is a way."

"Where there is a will, there is a way."

Can an Aggressive Dog Truly Be Rehabilitated After Biting?

Can an aggressive dog be rehabilitated after biting? As seen, there are several factors and variables to consider. These are just a few of the many variables that may play a role in successful rehabilitation.

Other variables may include the age of the dog (younger dogs are generally more malleable), how long the aggressive behavior has been rehearsed (the longer, the more difficult to eradicate), and whether there are children in the home (which are particularly vulnerable).

The ultimate answer to the above question is, therefore, "it depends." The prognosis is definitely graver in a dog that is large, has little bite inhibition, and a low-level bite threshold compared to a smaller-sized dog with good bite inhibition and a higher bite threshold.

Rehabilitation often takes extensive time before the dog appears to be nonreactive in specific circumstances, and there are chances that an aggressive dog with a bite history may never be entirely cured. Management, in those cases, may need to be a lifelong commitment.

The saying "Where there is a will, there is a way" should be kept in mind, too. Dog owners that are highly motivated to rehabilitate their dogs have been known to attain stellar results even with severe and complex cases, so this is something to definitely take into consideration.

What About Re-homing?

Re-homing is an option but mostly in the cases where the aggression is targeted towards stimuli or situations that can be fully controlled. For example, a dog aggressive towards other dogs is re-homed to a home with no other dogs, a dog who has killed cats is re-homed to a home with no cats, and a dog who struggles with young children is re-homed to a home with no children.

However, it must be considered that full disclosure must be given to the new owners, the new owners should also have a certain level of expertise with dogs and management remains a top priority considering that these dogs may still encounter other dogs or cats on walks.

Re-homing needs not to be taken lightly, you may be liable if your dog may bite when in the new owner's care.

What About Sending the Dog to Rescue?

Yes, you may stumble upon some rescues that have professionals work with aggressive dogs, but there is a lot of debate out there regarding how responsible and ethical this option actually is considering the risks of a dog not being entirely rehabilitated and the potential for setbacks once in a new home (considering that rehoming a dog is highly stressful and may lower a dog's threshold for aggression).

Many rescues also are operating at full capacity and may have long waiting lists. It, therefore, makes sense for them to reserve spots for dogs with less severe behavior problems which have a higher rate of rehabilitation. On top of this, one must consider what will the rescue do with the dog, will they truly put an effort to rehabilitate or just warehouse the dog?

What About Euthanasia?

Sadly, in some cases rehabilitation may be particularly risky and the risks at stake may be too high. A dog being a constant danger to himself and others or being in a constant state of stress may lead to a very poor quality of life. It's unfortunate but sometimes some dogs cannot be fixed. Euthanasia may therefore be considered, but only as a last resort once all resources have been exhausted.

Safety and Precautions

This article is not to be used as a substitute for professional behavioral advice. If your dog is aggressive, please consult with a behavior professional for safety and correct implementation of behavior modification.

It is helpful to start thinking about behavior problems as being like diabetic conditions. We do not cure diabetes, but we do an excellent job of controlling it. Regardless, after diabetes is controlled, no one would dream of withdrawing the insulin.

— Dr. Karen Overall


  • "Summary & Analysis: Investigating behavior assessment instruments to predict aggression in dogs," by National Canine Research Council.
  • "Evaluation of the Aggressive Dog: What is a Really Dangerous Dog?" World Small Animal Veterinary Association World Congress Proceedings, 2004, Patrick Pageat, DVM, PhD, Dipl Behaviorist FVS, DECVBM-CA.
  • University of Pennsylvania. "If You're Aggressive, Your Dog Will Be Too, Says Veterinary Study." ScienceDaily. ScienceDaily, 18 February 2009.
  • Herron et al. "Survey of the use and outcome of confrontational and non-confrontational training methods in client-owned dogs showing undesired behaviors." Applied Animal Behaviour Science, 2009.
  • "Oh Behave, Dogs" from Pavlov to Premack t Pinker, Jean Donaldson, Dogwise Publishing.
  • "The Culture Clash," Jean Donaldson, James & Kenneth Publishers.
  • Dr. Ian Dunbar’s Dog Bite Scale (Official Authorized Version). "An assessment of the severity of biting problems based on an objective evaluation of wound pathology."
  • "Clinical Behavioral Medicine for Small Animals," Dr. Karen Overall, Mosby 1997.

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

© 2018 Adrienne Farricelli


Adrienne Farricelli (author) on May 04, 2020:

Hi Ashley, these cases aren't easy as there are liabilities and risks when dogs have a history of repeated bites. It sounds like most bites directed towards you are re-directed bites, which tend to occur when we try to restrain a dog from biting a person or dog.

This happens when the dog is in a hyper roused state and bites instinctively at anything that gets in between him and the perceived "enemies" which is another facet to work on considering that he sounds under socialized.

Dogs in this hyper aroused state shouldn't be handled and safer ways to stop them should be found (hosing the dog with water, a loud noise to distract, or products such as Spray Shield, (although there are no guarantees they may work to prevent redirection and stop the dog).

In cases like yours, I would highly recommend an assessment by a veterinary behaviorist to determine prognosis (rule our medical conditions) and to gain some specific advice based on several factors on what options may be available, though as you state, I agree that there will always be a level of risk even in hands of experienced dog owners.

Ashley Gonzalez from Palm Desert on May 02, 2020:

I have a German Shepherd mix dog about 9 years old. He’s a rescue from streets of San Felipe, Mexico. My brother brought him over the border, and he was living with my parents and 2 brothers for some years confined to a small side yard with little interaction throughout the years that they had him. I recently took over ownership almost two years ago and he’s been living with me and my three-year-old son.

On April 29th, 2020 he had his 4th biting incident since living with me. He was barking on my front patio aggressively at two dogs that were being watched by their owner and he pushed up against the gate and somehow the latch opened up and he got out and was able to attack one of the dogs causing that dog to need surgery on a ripped tendon under his front leg. This is the most severe incident, and animal control is called and they are going to place a restraining order on the dog to stay on the premises or if off the premises must wear a muzzle and will it show me stricter guidelines once the City opens up and the restraining order is issued.

The third incident was in my grandparents backyard The Gardener was trying to come in and he had his lawnmower in between himself and my dog trying to get to him and when I pulled him back he bit my leg causing a puncture wound.

The second incident my son and I were walking the dog I’m speaking of and a smaller Chihuahua that he had previously lived with at my parents. The owner of the attacked dog on the 4th incident and her two dogs were walking and the Chihuahua had gotten loose from my son and ran up to the lady and her two dogs. My big dog was barking and trying to make his way by any means towards the dogs and the lady and I was calling the Chihuahua to come back to us but she wouldn’t come and I was trying to restrain the big dog and I pulled him back once and he bit my hand and I pulled him back the second time and he bit my leg. That bite to my leg was pretty bad just because it’s left a good scar.

The first incident was a bite to a gardener on my front lawn. My roommate at the time had let him out to go pee on the front lawn and he didn’t notice that there was a garter on inside of the truck parked in front of our House. My dog then saw her after he was done peeing and ran up to her and bit her on the hand and on the leg. That was the first time animal control is called and they gave me a fine to pay, a citation, and he was mandated to wear a muzzle when off the property.

My first option is to find a person that is willing to take him that has experience in obedience training or aggressive dogs and can handle this type of case and if they live out of the county that I am in animal control from Riverside county has to contact the new county and get permission that it is okay for my dog to move to that county.

My second option is to have him euthanized on my own terms with a vet and have him cremated.

My third option is to release ownership to animal control in Palm desert California and they said that they would be euthanizing him. I don’t know if they will keep him in a kennel until the City opens up and then euthanize him or if they will euthanize him right away.

Having him euthanized is not the route that I want to go for this dog because I feel that he has potential to be an obedient dog and a great addition to a single owner or a couple with some land or good space for him. Yet I know they should understand to stay on guard because you never know what will trigger an animal with these type of incidents that he has had and the life that he has lived prior.

I am seeking any and all advice and help if possible to keep my dog, Rico, alive and safe! Please contact me with any options that you may have available or help with the options that I have stated I have.

Lois Nielsen on October 11, 2019:

Thank you I will discuss all this with the trainer this afternoon and will for sure review those articles

Adrienne Farricelli (author) on October 10, 2019:

Lois, glad to hear you are enlisting the help of a professional. These cases require in person evaluations and guidance for safety and correct implementation of behavior modification. I hope the professional you chose is committed to force-free behavior modification as we don't want more stress added into the equation with the addition of aversive tools or techniques.

One little tip I can give is that when dogs are suspicious or fearful, I don't have people directly hand out the treats. I have noticed this causes some hesitancy and prompts what I call the "approach avoidance dance." This is a dog who is tempted but scared at the same time. What I prefer is having people toss the treat past the dog in the treat-retreat fashion.

It could be that your dog was really aiming for the gloves, but best to discuss that episode with the professional. This article may help you understand protective behavior better, but you'll need expert in-person coaching to tackle that.

Lois Nielsen on October 10, 2019:

I adopted. Blue heeler puppy at 14 weeks. Buckley is now 12 months and has been socialized, had two rounds of puppy classes and was house trained within a few weeks. Overall he is a happy fun puppy that loves to play and snuggle. He attends daycare two to three days per week and we walk daily. I am a single young senior and live alone although he always comes to work with me. At about 10 months I noticed the herding instinct kick into high gear. I do not have many male friends and find him extremely cautious around men. I keep treats on the counter at my office to when male customers come in they give him one. Some he is ok with and others he will take the treat and leave. Last week on the day of his first birthday he walked past a man with NO interaction turned his head and bit him hard and just kept walking. He knew right away he did something wrong. The man is fine and we have communicated regularly. He thinks that the puppy may have caught sight of a pair of gloves in his back pocket as he walked by. Otherwise there is no reason for him to what he did. My trust level has sunk to a new low but I try to keep positive. I am meeting a trainer next week to have him do an initial consultation. I have never had a dog bite anyone and completely at a loss. My other concern is can he be to protective of me and what do I do about that?