North Toronto Animal Clinic, Thornhill, ON, northtorontovets.com Diagnosis of fear aggression

Aggression toward unfamiliar pets or people is usually motivated by fear. Aggression may also be protective, possessive, or redirected but most of these will also have components of fear. Therefore, most treatment programs will require a similar approach. How a dog responds to a stimulus will be based on its genetics, socialisation and previous experience. Fear can be described as a conscious response to avoid a stimulus. 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. Some animals will freeze and others, because of uncertainty of how to respond may show conflict or displacement behaviors such as yawning, lip licking or circling. Fears are not necessarily maladaptive, but can interfere with quality of life and the pet-owner interaction. In fear aggression, the pet’s initial response to the stimulus would be associated with body postures and facial expressions that are consistent with fear. However, with time learning becomes a critical factor in how the problem progresses. Therefore, at the time of presentation the pet’s behaviour will have been modified by experience. For example, if aggressive behaviour leads to retreat of the stimulus or if the owner removes the dog from the situation the behaviour is negatively reinforced. If the stimulus is threatening, fearful or retaliates, or if the owner is anxious or punishes the pet, fear may b