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Dog Behavior Problems – Aggression - Unfamiliar Dogs – Treatment


A Gray/Brown Dog Biting its Leash Standing Outside

How can I prevent my dog from becoming aggressive with other dogs?

Prevention starts with puppy training and socialization. Early and frequent association with other dogs will enable your pet to learn proper interactions and reactions to other dogs. This can be very helpful in prevention of aggression to other dogs. Socialization must occur with other dogs that are calm and able to communicate well with other dogs, and should progress to a variety of shapes, sizes and personalities of dogs. Ear carriage, eye contact, tail position and even body postures may be difficult to “read” if there are significant size disparities, or if one or both of the dogs has cropped ears, hair that covers the eyes or a docked tail (see Canine Communication – Interpreting Dog Language). You must have good control of your dog. This means that your dog will take contextual cues from you, and may be calmer, less anxious, and less likely to be protective in the presence of new stimuli. Moreover, the dog should reliably respond to commands to “sit,” “stay,” and “quiet” so that appropriate responses can be reinforced rather than undesirable responses being punished (see Reinforcement and Rewards). If necessary, the dog may need a head halter to give you additional control (see Training Products – Head Halter Training and Training Products – Head Halter Training – Synopsis). When in situations where the dog may encounter other dogs, a leash is necessary.

"Because of the potential for injury, liability, and increasing the intensity of the problem, a behavior consultation would be advisable to structure the treatment plan."

For territorial behaviors, what is most important is to prevent the dog from engaging in prolonged and out of control aggressive displays in both the home and yard. Aggressive displays include barking, lunging, fence running, jumping on doors, windows and fences. These types of behaviors should be discouraged, or prevented by blocking windows if needed and going outside with the dog to prevent them. Using a leash and head collar both indoors and outside will increase control and allow you to interrupt aggressive responses and redirect the dog to more appropriate ones. One important component is teaching your dog a “quiet” command for barking (see Barking and Training “Quiet” and Barking and Training “Quiet” – Synopsis).

My dog is already aggressive toward other dogs. What can I do?

First and foremost, you must have complete control over your pet. This not only serves to calm the dog and reduce its anxiety, but also allows you to successfully deal with each encounter with other dogs. Fixed length (not retractable) leashes are essential and the use of head collars and/or muzzles are strongly recommended for dogs that will be in situations with multiple dogs. Because of the potential for injury, liability and increasing the intensity of the problem, a behavior consultation would be advisable to structure the treatment plan. Until you have more control and a treatment plan in place all encounters with other dogs must be avoided. Begin by establishing reliable responses to basic obedience commands. If the dog cannot be taught to display a relaxed 'sit', 'stay', 'come' and 'heel' (see Teaching Calm – Settle and Relaxation Training and Teaching Loose Leash Walks, Backing Up, and Turning Away), in the absence of potential problems, then there is no chance that the dog will respond obediently in problematic situations. Reward selection can be critical in these cases, because the dog needs to be taught that obedient behavior in the presence of the stimulus (other dog) can earn the dog-favored rewards (for most dogs this is a food treat such as cheese, small pieces of hot dogs etc.). The goal is that the dog learns to associate the approach of other dogs with rewards. Long term treatment consists of desensitization (gradual exposure) and counter-conditioning the dog, so that the approach of the other dogs leads to a positive emotional response (see Desensitization and Counter-Conditioning, Implementing Desensitization and Counter-Conditioning – Setting Up for Success, and Fears and Phobias – Animals and People).

"The goal is that the dog learns to associate the approach of other dogs with rewards."

In training terms, the dog must be taught to display an appropriate, acceptable response when other dogs approach (e.g., “sit,” “watch,” “relax”), which can be reinforced (differential reinforcement or response substitution). This must be done slowly, beginning with situations where the dog can be successfully controlled and rewarded, and very slowly progressing to more difficult encounters and environments. The first step is to conduct training for its favored rewards in a situation where there are no dogs present and training will proceed successfully. Initially, food or toy prompts can be used at first to get the dog’s attention, but soon the rewards should be hidden and the dog rewarded intermittently. The selection of favored food or toys is essential since the goal is that the dog will learn that receiving these favored rewards is contingent on meeting other dogs. A leash and head collar can be helpful to increase control and aid in compliance with training. During this pre-training, exposure to other dogs must be avoided since ongoing expression of the behavior tends to reinforce it. Once the dog responds quickly and is receiving rewards on an intermittent basis, training should progress to low-level exposure to other dogs. If the owner's training and the rewards are not sufficient to control the dog in the absence of the other dogs, then utilizing a leash and head collar, selection of more motivating rewards, and seeking the assistance and guidance of a behaviorist should be considered. The next steps in desensitization and counter-conditioning rely on a stimulus gradient. In other words, your dog needs to be under control (preferably with fixed length leash and head halter) and respond to commands and rewards in the presence of gradually more intense stimuli. Start low, mild, and work up to gradually more intensity. Find the threshold at which your dog might begin to display fear, anxiety or arousal and keep to a level of intensity that is mild enough that the pet remains calm and responsive to training so that you can give favored rewards for success. The goal will be to increase the increment of intensity only a level where your dog remains sufficiently calm that it can learn and receive favored rewards for each exposure. Keep in mind that distance is often a factor, so initially the stimulus must be far away. Remember it is better to keep sessions short rather than risk an unwanted response.

"Success can be achieved in a number of ways, but head halters are generally the most important tools."

Begin with a calm and well-controlled second dog, in an environment where your dog is the least anxious or threatened, and at a sufficient distance to get your dog to respond to your commands (sit, loose leash walk, back up or turn away), (see Teaching Loose Leash Walks, Backing Up, and Turning Away). Gradually, expose your dog to other dogs at closer distances and in more familiar locations. Using the head halter and a prompt (lure reward, favored toy, set of keys) it should be possible to keep the dog focused on the owner and sufficiently distracted. While dogs with fear aggression may improve dramatically, dogs that are very assertive and are trained in this manner do not necessarily get better about greeting other dogs, but should learn to walk calmly with their owners and not initiate fighting behavior. By training the dog for rewards in the absence of the stimulus, using a head halter, and beginning exposure training with low enough levels of the stimulus, your dog should be calm enough to focus, settle and learn that the other dog is not a threat.In fact, with counter-conditioning (favored rewards paired with association with the stimulus) your dog should begin to enjoy meeting and greeting other dogs. If your dog remains too fearful, excited, aroused or out of control, you will need to consider further training prior to exposure, a head halter (if you are not already using one), lower levels of stimulus exposure (e.g., a less intense starting point for desensitization) or perhaps drugs to help your dog calm and focus (see below). Dogs that are exhibiting territorial aggression are retrained in much the same manner, but the gradient of stimuli needs careful control. Begin in the front hall or on the front porch with no other dogs around. Then with the dog controlled in the hall or on the porch, other dogs are brought to the perimeter of the property. Over subsequent training sessions, the dogs could be brought closer to your dog, or your dog could be moved closer to the other dog (see Implementing Desensitization and Counter-Conditioning – Setting Up for Success). Another way to disrupt the undesirable response in territorial aggression, and get the dog's attention is to use an air horn, shake can or citronella spray collar. If the dog barks before the aggressive display, the barking will activate the citronella spray collar, ensuring immediate timing and disruption; if the barking is inhibited, the behavior may not progress. Once the inappropriate behavior ceases, and you get your dog's attention, the dog should be redirected to an appropriate behavior such as play. The greeting should be repeated, until no aggression or threats are observed. Success can be achieved in a number of ways, but head halters are generally the most important tools. Head halters provide enough physical control that the desired behavior can be achieved (sit, heel) since pulling up and forward, turns the head toward the owner and causes the dog to retreat into a sit position. With the dog's head oriented toward the owner and away from the other dog, lunging and aggression can be prevented, and the dog will usually settle down enough to see and respond to the prompt. A second hand can guide the muzzle under the chin to ensure eye contact and help to calm the dog. Rewards can and should be given immediately for a proper response (sitting, heeling), by releasing tension on the leash. If the dog remains under control with the leash slack, the reward (toy, food, affection) should be given, but if the problem behavior recurs, the leash should be pulled and then released as many times as is necessary to get and maintain the desired response. If however, that is not possible, then the stimulus is too intense and it may be necessary to leave the situation or if possible send the approaching dog away. When the training program is done properly, the dog's anxiety quickly diminishes. Learning occurs, and the dog realizes that the other dog is not to be feared, that there is no opportunity to escape, that its responses will not chase away the other dog, that responding to the owner's commands will achieve rewards, and that the owner has sufficient control to achieve the desired behavior (which further calms the dog). In addition, since there is no punishment or discomfort that might further aggravate the situation, and rewards are not being given until the desired behavior appears, fear and anxiety will be further reduced (see Training Products – Head Halter Training).

Are there drugs that can help the treatment program?

Occasionally, for fear aggressive dogs in particular, anti-anxiety drugs may help to calm the dog enough so that the retraining session is successful. Dogs that are too highly aroused may be unable to focus, settle and learn that other dogs are not a threat. For situations where the problem has become highly conditioned and intense, antidepressants may be useful for regaining control. In most cases however, the best calming influence is a head halter, good owner control and some strong rewards. Caution should be exercised with medication because medicine alone will not teach the dog proper responses.

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