Treating canine fear aggression behavioral management and products (Proceedings)

How a dog responds to a stimulus will be based on its genetics, socialisation and previous experience. How the stimulus and owner respond may further reinforce or aggravate the situation. For example, if aggressive behaviour leads to retreat of the stimulus or the owner removes the dog from the situation the behaviour has been negatively reinforced. On the other hand, if the stimulus is threatening, fearful or retaliates, or if the owner is anxious or punishes the pet, fear may be further conditioned.

Diagnosis of fear aggression

Dogs respond to fear evoking stimuli with either aggression (fight) or retreat (flight), both intended to increase the distance between the stimulus and the dog. While the response may initially be associated with body postures and facial expressions that are consistent with fear, dogs with fear aggression may quickly learn that the aggression is a successful means of removing the threat, and may progress to more bold and offensive signaling. Therefore the history, beginning with the first event and progressing to the present, as well as the ABC's of behaviour (antecedent, behaviour, consequence) are necessary for both diagnosis and to formulate a treatment plan. In any behaviour case, the veterinarian should first rule out medical causes.

Treatment of fear aggression

When anxiety and arousal is high the pet will react automatically to the threat so that behaviour modification is impractical and new learning cannot occur. Therefore, an initial starting point for exposure requires the owner begin exposure with a minimum level of stimulus intensity (desensitisation), use high enough value rewards to motivate the pet to exhibit a desirable behaviour that is incompatible with the fearful response (response substitution) and to condition a positive emotional state (counterconditioning). Drugs or natural supplements may also be necessary, not only to reduce the fear and anxiety so that the pet can learn, but also for the well-being of the pet.

The first step in any consultation is to determine whether safety can be insured and to discuss what realistically can be achieved. The prognosis will be based on the owner's ability to prevent further injury, the potential for achieving improvement through environmental management and behaviour modification, and whether products or drugs might be useful.

The consultant should then insure that the owners have a good understanding of how pets learn and how they perceive owner responses. The goal of training should be to reinforce what is desirable and to ignore or avoid those behaviours that are undesirable. Positive reinforcement requires immediacy, consistency and contingency, and a calm, quiet approach. Over time, the owner should use the rewards to gradually shape behaviours that are more relaxed and of longer duration. The focus of the training should be to develop strategies for successful, safe and positive exposure to the stimulus.

1. Preventive management

Before instituting behaviour modification, the owner must first put in place a means of preventing or avoiding further exposure to the stimulus, both to insure safety as well as to avoid further learning and conditioning. Prevention might accomplished by keeping the dog on leash at sufficient distance from the stimulus, confining the pet away from the stimulus, or applying a muzzle for safety. A head halter could also be used to turn the head, close the mouth and remove the pet from potentially problematic situations. Sometimes preventive measures are required long term or permanently (environmental management), while some situations can be improved or managed with behaviour modification.

2. Management and training

a) For fear aggression to be effectively treated, exposure to the stimulus with a positive outcome will be required. However, the owner must first gain verbal and physical control of the pet with reinforcement based training and the aid of any behavioural tools that might better achieve success. The initial goal is to be able to calm and settle the dog in the absence of the stimuli with minimal distractions. The owner should train behaviours that will be most practical for successful implementation of exposure exercises. For outdoor exposure these might include a) calm sit / watch, b) relaxed walk or c) back up or turn away. For indoor exposure and a calm sit / watch, d) relaxed down, or e) mat (place, bed, crate, room) exercise might be most practical. A reliable come is also needed if the pet is ever to be off leash. The owner should work to shape gradually longer duration and greater relaxation (by monitoring breathing, body language and facial expressions).

b) Training should focus on reinforcement of what is desirable, while ignoring or preventing those behaviours that are undesirable. From the outset owners should be counseled as to what might serve to reinforce their pets and to make a gradient of rewards. The highest level reward should be used to reinforce each new step or progression in training, while lower level rewards can be used to reinforce previously learned responses. (No need to overpay). Rewards are anything that the pet finds desirable. The program (learn to earn, nothing in life is free) focuses on teaching the pet what behaviours achieve rewards. This can be accomplished by having owners cease all casual interactions and insure that desired behaviours are learned each time the dog solicits an interaction (e.g. attention, play, walk, food soliciting). Thus any time the pet and owner are together, training is taking place. The dog should learn what behaviours achieve rewards (to provide control and predictability). For example, sit or down should precede affection (including greeting), feeding, play, going outdoors or crossing the street. Most dogs who pull merely need to learn that a walk (which is the reinforcer) will not proceed unless the leash is slack. A chew or feeding toy might be used to reinforce and encourage an extended down stay or mat exercise. Food, treats, or a play toy can be saved to lure and motivate the pet to initially achieve any behaviour.

3. Behaviour Management Products

A head halter serves to communicate the owner's intentions by prompting the dog to achieve the desired response. In addition, by controlling the muzzle and mouth, biting, barking and lunging can be more safely and effectively prevented. Head halters can be used to a) reorient the head to focus on the owner and away from the stimulus b) prompt the dog to exhibit desirable responses which can be positively reinforced c) help the owner progress to longer and more relaxed responses d) reinforce desirable behaviours and insure proper timing with an immediate release of tension (negative reinforcement). Products that prong or shock may suppress behaviour but do not help to achieve desirable responses and may exacerbate conditioned fear or anxiety. Body harnesses which attach at the front of the chest are useful for pulling but do not control the head and muzzle which is usually a necessity in fearfully aggressive dogs. Clicker training (where a clicker is paired with a favoured food reward) can be used to immediately mark and shape desirable behaviours as well as to countercondition. If a head halter or clicker will be used during exposure exercises, they should be used from the outset, so that both the owner and pet are familiar with the products and techniques. Target training is another alternative. The pet can be lured using a target that has been paired with a favoured treat. A calming cap covers the eyes and partially reduces visual stimuli for desensitisation.

Once these behaviours can be reliably achieved in the absence of the stimuli, then training should proceed to include more distractions and locations. The owner can set up training with familiar people or dogs to insure that they can achieve desirable behaviours. Should the dog become excited, then the efficacy of the training (and the head halter) can be safely put to the test. When relaxed and calm target behaviours can be reliably achieved with a variety of distractions and locations, training can progress to actual stimuli.

4. Stimulus Exposure

Using a stimulus gradient (visual, auditory, odour), the lowest level of stimulus and the highest level of rewards are used for initial exposure (desensitisation and counterconditioning). Stimuli can be muted and modified by a) distance, b) stimulus characteristics (e.g. uniform, height, age, etc) c) location e) intensity (e.g. motion, volume) and d) by separating stimuli into component parts e.g. bikes, person, person on bike, motion, etc). Horizontal movements of the stimulus (i.e. back and forth rather than coming at the pet) can also help to reduce intensity. Fear can also be minimized during initial exposure if the stimulus remains still, calm, and quiet or slow moving. In addition, the person doing the training should initially be the one who can most likely calm and control the dog during exposure. If a calm behaviour (response substitution) and a positive association (counterconditioning) can be achieved, then the owner can gradually progress to more intense stimuli. A back out or let's go after a successful sit/ focus can be used to insure that the pet ends the session on a positive note.

When the stimulus intensity or the pet's fear, anxiety or arousal is too high to be able to calm the pet for desensitization and counterconditioning, the use of medications may be warranted. These will be covered in a later seminar.

References

Pryor, K. Don't shoot the dog. Ringpress Books Ltd., Gloucestershire, 2002

Rogerson, J. Canine fears and phobias; a regime for treatment without recourse to drugs. Applied Animal Behaviour Science 1997; 52: 291-297

Horwitz, D. Classical counterconditioning as a treatment modality for dogs (Canis familiaris) showing aggression toward other dogs on walks. In: Current issues and research in veterinary behavioral medicine. Mills, D et al (eds), Purdue Press, 2005; 207-210