Assessing the risk of injury of aggressive dogs (Proceedings)

One of the most crucial steps in working up a dog aggression case is assessing the danger inherent in the situation. A very complete history should be taken from all family members and others involved with the pet. But even when meticulous care is taken to collect information, it may not always be possible to obtain all pertinent details. For example, no adults may have been present to see what triggered the bite of a very young child. Or, the family may know how the pet interacts with adults, but since the pet has never been around children, the danger the pet might pose to them is unknown. The less that is known about the pet's social behavior around different types of people in various situations, the more questions remain about the amount of danger it poses. In cases where significant danger is obvious or in those where the data is insufficient, exceptionally safe and conservative management will be required.

Variables correlated with danger

• Predictability

• Potential to cause damage

• Characteristics of the family

• Overall complexity of the situation

Predictability

The ability to safely manage an aggressive pet depends a great deal on knowing when it will bite. In order to determine predictability, behavior patterns and triggers for aggression must be identified. It must also be determined whether the pet's behavior in these situations is consistent. If it is known that touching the pet's head causes it to bite, but not all of the time, danger may increase because people tend to let their guard down when the pet is not consistently aggressive.

The type of stimulus that causes the pet to be aggressive is also important. Most people realize that a strong stimulus, such as kicking a dog, will likely cause aggression. On the other hand, many would not expect to be bitten if they calmly bend down, eye-to-eye to a dog and pat it on the head. So, danger increases when "benign" stimuli trigger aggression.

The absence of warning signals also increases the risk of injury. A person is less likely to avoid being bitten when there are no signs predicting aggressive behavior. Another issue is the latency period between the beginning of the warning and the attack. It doesn't help the victim if the pet gives a warning, but attacks a millisecond after the warning begins.

In situations where the triggers for uninhibited, injurious bite behavior are completely unknown, it must be assumed that the pet could be aggressive at any time. No contact with people can be permitted, and the pet may need to be muzzled at all times or locked in a safe confinement area.

Potential to cause damage

The physical aspects of the dog are certainly important factors in assessing the potential for damage. It's obvious that large, strong dogs can cause the most damage, but the degree of bite inhibition the animal exhibits is also important. In assessing risk of injury, the amount of bite inhibition the dog displays is typically more important than the frequency with which bites occur. If a large pet has bitten a variety of people in a variety of situations many times and has caused nothing more than light contusions, it is in all probability a safer pet than a smaller one that is unable to inhibit the force of its bite and, even though it has only bitten a few times, has caused serious injuries such as deep tears or broken bones. The number of bites per incident is another important variable. Dogs that bite multiple times during aggressive incidents are likely to be more dangerous than those that bite once and retreat.

The intensity of focus and level of arousal the dog exhibits toward the target during aggressive situations is also important. When these are mild, the owner is more likely to be able to intervene and control the pet. Interrupting a dog that is very aroused and orienting strongly can be exceptionally difficult and an injury will be more likely. The amount of training and dependability of command responses also has an effect on safety.

The target of the aggression is another consideration. Young children and babies are more easily injured with less force than are adults. The type of aggression being displayed can determine the amount of damage done and influence the amount of danger that exists. Predatory-related aggression is the most dangerous type, since killing is part of the behavioral sequence. Territorial aggression is usually more dangerous than fear-related aggression because a dog exhibiting territorial aggression often will pursue the victim. A fear aggressive dog is more likely to avoid interaction and only be aggressive when its personal space in penetrated and there is no opportunity of avoidance.

The human element

Characteristics of the family can be very important variables influencing the danger of the situation. Some families are in denial about the pet's behavior and take more risks. The amount of activity and complexity of schedules in some households makes safe control and management of the pet difficult. Large families or those with young children often have difficulty providing safe supervision or confinement of the pet. Doors are left open, locks on gates are forgotten, supervisory duties are not consistent. Families with children may have visiting children in and out without adults knowing. Homes with cognitively impaired adults or young children may have family members that are more likely to put themselves at risk without realizing it and less likely to understand treatment regimens.

The experience of the family with dogs in general is important. The more experience family members have living with dogs, the more they are likely to know about what types of behavior to expect and how to appropriately interact with the pet. They are also more likely to be aware of subtle signs of threatening or aggressive behavior, as well as what constitutes a dangerous situation.

Overall complexity of the situation

Finally, the degree of complexity of the entire situation can have an effect on the danger that is present. If there are many types of aggression being displayed by the pet, and if there are a wide variety of stimuli that trigger aggressive behavior, the danger increases. The presence of other concurrent behavior problems also may increase the risk that aggression will occur. For example, if the owner of a pet with a fear-related aggression problem is upset about destructive behavior or housesoiling, the person might be likely to react impulsively in a way that will elicit an aggressive response from the pet. As the number of confrontations with the pet increases, the likelihood of aggression and injuries increases.

Summary

Once a behavioral history is obtained for an aggressive dog, the next critical step involves assessing the level of danger and, in particular, whether that danger can be controlled. This has to be done before entering into a discussion of a treatment plan. Variables relating to the risk of injury the pet poses and whether the owners can control the opportunity for interaction with target people or animals will determine if the pet should stay in the home, be rehomed or be euthanized.

A large, strong dog that bites children unpredictably without inhibition in a busy home with many small children, and poor supervision by adults who cannot comprehend the danger of the situation, will obviously pose an extremely high risk for a serious injury. Removing the pet from the home will be a priority in this case. Euthanasia may be a necessary choice, although rehoming may be an option in select cases. In situations where the risk of injury is mild to moderate and can be controlled, the consultant can progress on to a discussion of treatment options.

References

Reprinted with modification from Handbook of Behavior Problems of the Dog and Cat, 2nd Edition, Landsberg, Hunthausen, Ackerman (2003) Saunders Pub.