Ms. G’s dog, Tommy, was slowly becoming grossly overweight. He weighed 10 lb more than the last time I saw him and at least 20 lb more than he should weigh. “Tommy needs to pass on the midnight snacks,” I told her, “but just as important, he needs to be getting more exercise.”
Ms. G appeared distressed as well as concerned. “I know he needs more exercise,” she said, “and I want to get him out more. But he’s a big boy and I just can’t control him when I walk him on a leash. He constantly barks and lunges at everything he sees. It’s so embarrassing!”
Ms. G is not alone in her dilemma. Reactivity on a leash is a common canine behavior problem and is often stressful for owners. It can be caused by a variety of underlying problems, including aggression, fear, unruliness, play-soliciting behavior, or inadequate training. The problem can usually be successfully treated if the owners have the commitment, tools, and correct information to get the job done. Outlined below is a typical plan that I use to address this problem.
The purpose of these exercises is to give owners more control over their dogs on walks and to replace lunging, barking, or aggressive or fearful behaviors with calm, quiet, and relaxed behaviors. Training at a distance beyond the response threshold (see “Response threshold distances” below) is absolutely necessary. Dogs are less manageable and have difficulty learning when they are highly aroused.
Owners need to stay as relaxed as possible and think of these exercises as games to play with their dogs. If aggression is part of a dog’s reactive behavior, the person walking the dog is responsible for others’ safety and must ensure that leashes and halters are secure and that there is no opportunity for physical contact with other dogs or people.
Before the social conditioning process begins, the dog must be taught to dependably come, sit, stay, and heel on a leash. This training may require the help of a private trainer since these dogs usually do poorly in a class situation. It should be noted that throughout the entire training process, only positive reinforcement types of training techniques should be used.
Next, owners need to teach their dogs that they are in control. By setting boundaries, the owner will obtain better compliance and dependability from obedience cues. This can be accomplished by initiating a social structure or a nothing-in-life-is-free program.
As part of this program, the owner should request that the dog sit before getting anything it wants or needs, the dog should be ignored when it demands attention, and the dog should frequently be asked to stay before being allowed to follow owners around the home or yard or before going in or out of the home. During training, all commands should be given in an upbeat and relaxed tone of voice.
In addition to having a social conditioning plan (see “Phase 1: Counterconditioning at a distance” below to begin the training plan), other tools that owners will need when training their dogs against reactive behaviors are positive reinforcers and instruments for maintaining physical control (e.g. an appropriate leash, a head halter).
Reinforcers. Owners must determine their dogs’ most desirable food (e.g. very tasty dog treats, freeze-dried liver, cooked chicken or turkey, cheese, fat-free turkey hot dogs) and give that food only during the dogs’ social and obedience conditioning training. It is helpful to always say a specific word or phrase, such as “good dog,” as the food is given. By frequently associating specific words with food, the words can be used as relatively strong reinforcers even when food is not present.
Physical control. To maintain physical control of dogs during training, owners should keep their dogs on 4- to 6-ft leashes. Owners should have one hand in the loop, and the other hand should be holding the leash a few feet from the collar. Retractable leashes are unreliable and unwieldy and should not be used. Devices that cause discomfort—such as pinch collars, shock collars, and choke collars—should be avoided because owners want their dogs to develop positive associations with people or other dogs they react toward and avoid unpleasant associations. Leash corrections or leash pops are not appropriate.
If more control is needed, the dog should be trained to wear a head halter. Owners may also consider a basket muzzle if there is any chance an aggressive dog might inadvertently have contact with another person or dog.
Response threshold distances
There are two threshold distances of concern: orienting threshold distance and reactive threshold distance. Training takes place between the two threshold distances.
The orienting threshold distance is the distance at which the dog barely recognizes and begins to focus toward the trigger stimulus (e.g. dog, person, bike). This distance should be significantly farther than the distance at which the owner begins to lose control of the dog.
The reactive threshold distance is the distance at which the dog begins to exhibit the unwanted behaviors (e.g. barking, growling, lunging). This distance may vary depending on the stimulus. For example, a dog that is aggressive to people might be reactive to most men at 100 ft but reactive to men with hats at 60 ft. Or a dog that is reactive to other dogs might react to large dogs at a farther distance than it does to small dogs.
Phase 1: Counterconditioning at a distance
Owners should begin by walking their dogs in relatively quiet spots where trigger stimuli appear intermittently. (See the sidebar “Training away from the neighborhood.”) Crowded areas should be avoided. Varying the time of the walk can be helpful, but owners should make sure it is at a time when there is a low density of people or dogs. Owners should be careful to keep their dogs beyond the reactive threshold distance.
When a dog orients toward a stimulus, the owner should immediately say the dog’s name in an upbeat tone and present a treat at the same time. The owner should request the dog sit or stay for no more than two seconds, give the treat, and say, “good dog.” The owner and dog should then continue slowly walking ahead. When the dog orients toward the stimulus again, the sequence should be repeated.
Before the stimulus crosses the second threshold distance (reactive threshold distance) and the dog becomes reactive, the owner should turn with the dog and walk in the opposite direction or down a side street. Over time, the dog should gradually be allowed to get closer to the stimulus before changing direction. (Hint: The dog is getting close to its personal reactive threshold if it takes the treat slowly or overly rough or fast, is slow to sit, whines, yawns, or maintains a strong focus on the stimulus even while taking the food.)
Phase 2: Passing by across the street
Once the dog will consistently perform a relaxed sit or stay about 40 ft from the stimulus, the next step is to continue to walk straight ahead but across the street from the stimulus as the stimulus passes in the opposite direction. The owner should request the dog sit or stay for treats several times as he or she walks the dog in the direction of the stimulus. When about 40 ft from the stimulus, the owner should place a large treat in front the dog’s nose, repeatedly say “heel” in an excited and upbeat tone, and briskly walk forward, keeping the dog oriented toward the food and its nose pointing straight ahead.
Phase 3: Sitting or staying beside the sidewalk
When the dog consistently ignores the stimulus across the street, the owner can proceed to Phase 3. As the stimulus approaches directly toward the dog from the front, the dog is commanded to sit or stay at a position about 20 ft to the side of the sidewalk. A treat is held in front of the dog’s nose until the stimulus passes, and then the dog is given the treat and released. An alternative approach for a dog that might have difficulty maintaining a long stay would be to have the owner give a series of sit or stay cues for treats as the stimulus passes. Slowly and gradually, the dog moves closer to the sidewalk during subsequent passes.
No scolding. Owners should avoid scolding dogs or saying, “leave it,” “watch me,” or “look at me,” in tense or agitated tones as a stimulus approaches. These types of responses will typically increase a dog’s arousal and reactivity. Owners should maintain safe control, stay beyond the reactive threshold distance, be calm but firm, and try to keep the leash as loose as possible.
Exhibiting reactive behavior. If a dog exhibits a reactive behavior (lunging, barking, growling) during a walk, the owner should immediately turn and briskly walk or jog out of the situation. The owner should be firm and calm and not yell, scold, give a leash correction, or punish the dog.
Stranger petting. If a dog has a history of aggression or a strong fear response and someone asks to pet the dog during a walk, the owner should decline. However, if the owner, the approaching person, and the dog are all relaxed, the owner can say, “I’m training this dog, so you can’t pet him, but would you mind tossing treats to him when I ask him to sit?” and allow the person to toss a treat to the dog. If anyone, including the dog, is not relaxed, the owner should decline the request, maintain a safe distance, and walk away with the dog.
Territorial behavior. Allowing a dog to aggressively lunge, bark, or growl while standing at windows, fence lines, or on tie-downs in the yard will undo the training done on walks. The dog should not be given the opportunity to perform these behaviors. Preventing or blocking access to window, doors, and fences can prevent this behavior. If this is not possible and the reactive behavior occurs, it should be interrupted. That can be done by having the owner use novel, loud noises that are appropriate for the dog’s temperament (e.g. a shake can, a hiker’s emergency whistle, InteroSTOP—Meridian Animal Health, an air horn) or by having the dog wear a citronella spray antibark collar. Shock collars should be avoided.
Once the dog stops the unacceptable behavior, it can be redirected to another acceptable behavior. The owner should always reward the dog with praise or a treat if the dog notices dogs, people, or other stimuli passing by the home and does not react.
Medication. Drugs may be necessary for dogs with unstable temperaments or for dogs in situations in which it is difficult or impossible to stay beyond the reactive threshold distance (e.g. dogs with extremely long reactive threshold distances, dogs that live in condominiums or apartment complexes, dogs that must be walked in crowded urban areas).
If medication is needed, I usually prescribe a selective serotonin reuptake inhibitor (SSRI). Owners can give fluoxetine, paroxetine, or sertraline to their dogs at 0.5 to 2 mg/kg once a day.
Since SSRIs can take up to six weeks to become effective, I often recommend that owners give dogs a second medication as needed to reduce arousal. For those situations, clonidine (0.01 to 0.05 mg/kg b.i.d.) or trazodone (2 or 3 mg/kg q.i.d.) given about an hour before walks can be helpful. Start at a low dosage and increase to effect.
Trazodone has an effect on the serotonin system, so lower dosages may be required for effect and to avoid serotonin syndrome, a serious and potentially fatal condition that may arise when antidepressants that inhibit serotonin reuptake are given at high doses or in combination with other drugs and dietary supplements that may increase serotonin. The serotonin syndrome results mainly in neurologic, autonomic, and gastrointestinal signs, including restlessness, mental confusion, hyperesthesia, shivering, shaking, hyperthermia, tachycardia, tachypnea, abdominal pain, diarrhea, vomiting, hypersalivation, twitching, tremors, seizures, coma, and death.
Pretreatment and follow-up diagnostic tests should be considered depending on the age and health of the dog, the type of medication given, and if multiple drugs are being administered concurrently.
The duration of training required to resolve this type of problem depends on the pet’s temperament, the duration of the problem, the severity of the problem, and the expertise and time dedicated by the owner. Training may take several weeks to many months. The owner needs to understand this and that patience is very important. Attempting to rush the dog through the treatment stages may actually delay progress and can be dangerous if aggression is involved. Encouragement and timely follow-ups or progress reports from the owner can be essential for accomplishing a satisfactory, safe outcome.
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