by Dr. Lindsey Workman
Aggression, whether directed at people or other animals, can be a frustrating and intimidating behavioral problem to deal with. National Dog Bite Prevention Week occurs this May. According to the American Veterinary Medical Association, there are 4.5 million people bitten by dogs each year with at least half of the victims requiring medical attention being children under the age of 14. In addition to the physical and emotional trauma of a dog attack, dog-bite wounds can lead to significant infection. Owners of a dog that attacks people or other animals may face significant repercussions including quarantine of their dog if he or she is not current on rabies vaccination and litigation.
Determining the type of aggression your dog is displaying and identifying potential triggers may help to better understand how to resolve the behavior. Signs of aggression in dogs can include signs of fear (cowering, trembling, ears down, tail tucked, urination/defecation/anal sac expression), raised hackles (hair along back), baring teeth, growling, staring, barking, lunging, and biting. Some causes of aggression can include dominance, fear, pain, play, predatory, and maternal-related aggression.
With dominance-related aggression, a dog is attempting to assert a higher social role above his or her victims. Dominance-related aggression is more prevalent in intact males and usually develops at social maturity (one to three years). Dogs showing dominance-related aggression may guard resources, block access to different areas of the house/yard, respond aggressively to any type of punishment, or respond to perceived dominant displays from humans such as staring or reaching over the dog. Some dogs may display only resource guarding in which they are protective of food, specific toys or objects, or even their owner.
One of the more common reasons for aggression in dogs is fear-related aggression. These pets will usually show signs of fear such as trembling, yawning, lip-licking, cowering, pupil dilation, tucking of the tail, and laid back ears, urination/defecation/anal sac expression. The aggression is also more commonly directed at people or animals the dog does not know.
Fear can also play a component in a dog showing aggression due to physical pain. In addition to pain, a dog may display signs of aggression due to other medical problems such as brain disease. Pain- and medical-related aggression should be considered in an older dog that has not previously displayed signs of aggression.
Play-related aggression develops when a dog does not respond to or display appropriate social signaling when playing, which would normally prevent escalation to inappropriate aggression. These dogs may have had inadequate socialization when puppies.
Predatory-related aggression develops from a dog’s internal instinct to catch prey and can be more prevalent in certain breeds. Predatory aggression will usually be directed at a victim that is small, moving rapidly, or producing high-pitched noises.
Finally, maternal aggression stems from a dog’s hormone driven desire to protect her young and is usually strongest the first week after giving birth.
Successfully managing your dog’s aggression involves communication with your veterinarian and, potentially, a canine behaviorist. Your veterinarian will want to rule out potential medical causes for aggression with a physical exam to identify any sources of pain, potentially a more indepth neurologic exam, and basic blood work. Once medical problems have been ruled out or managed, it is important to identify triggers for your dog’s aggression such as food, toys, strangers, and specific movements or body postures of the victim. Once potential triggers have been identified, determine whether these triggers can be avoided or changed to manage your dog’s aggression. This may include steps such as separating pets when eating or receiving treats and removing or putting high value toys in a secure place.
If a trigger cannot be eliminated from your dog’s environment, you will need to alter the trigger and/or counter-condition your dog to the trigger. This may include things such as altering body posture or ways in which you or others handle your pet to avoid perceived threatening movements and removing your dog from the home entrance when visitors arrive. Counter-conditioning involves training in which you seek to replace negative associations for a specific trigger with positive associations. This can include giving treats when a normally fearful trigger is present (as long as pet is calm and behaving). It is also important to teach your pet alternate behaviors and commands such as sit, stay, leave it, and give so you can attempt to redirect their behavior when they are starting to show signs of aggression.
In addition to managing triggers that result in your dog’s aggression, it is important to manage any anxiety your dog may have as this can lower the threshold at which they respond to situations aggressively. This can include environmental enrichment such as adequate exercise and puzzle toys and even medications to reduce anxiety. When managing your dog’s aggression, it is important to realize that in most cases punishment should be avoided. While punishment may temporarily stop a dog’s aggression, it may worsen the underlying fear motivating the aggression and increases risk of injury to the person punishing the dog. Although aggression can be a difficult problem to deal with, it is important to seek help from your veterinarian at the first signs of aggression.