The fight or flight response is any animals survival mode. The autonomic nervous system controls a number of body systems including the respiratory and cardiovascular systems. When the system is activated, the body increases respiratory and heart rates, increases mental alertness and decrease digestive activity so that the blood might be utilized in skeletal muscle tissue for quick movement and defense. The fight response occurs when the animal turns to take on the aggressor. The flight response occurs when the animal flees from and escapes the aggressor.
Where dominant aggression in dogs is similar to the fight portion of the flight or fight response of all animals, including humans, fear aggression is most closely related to the flight portion. A dog that is fear aggressive will become violent or aggressive literally to fight its way out of situation where it feels threatened or out of control. Dogs that were trained as attack dogs are generally fear aggressive dogs. The handler is the only individual the dog trusts. Each time the dog is greeted or approached by a stranger, a shock is administered to the animal. Through this stimulus response technique or classical conditioning, the dog learns that the presence of anyone except the handler is undesirable and becomes aggressive as a fear response. As the intensity of the fear or even the perception of fear increases so does the aggressive behavior. Without being trained to be fear aggressive there are other factors that could cause an animal to be fear aggressive including limited social interaction with humans and animals during the critical period of development.
The body language associated with fear aggression is similar in cats and dogs. Instead of pricking the ears as was the case in dominant aggression, the ears are laid back and the animal will crouch lower to the ground. Hair standing on end serves to make the animal look larger to the threatening animal. Dilated pupils are another cue from the frightened animal. As a worker in the animal care field, an ability to read these cues and understand them is critical to safety of both the animal and the employee. Fear aggression behaviors could be the result of injury or sickness. Animals who are cornered without an avenue for escape could also exhibit these behaviors attacking the person who is in the path of escape. This is called redirected aggression.
Many of the aggressive behaviors discussed become magnified when a dog or cat is brought into a situation where they may have had prior experience or learned that they should be fearful. The most common and necessary of these places is the veterinarian’s office. When all of the components of an office visit are considered from an animal’s point of view, it is a threatening environment that will invoke the fear or the dominance/defensive aggression. There are smells from other animals, both well and unwell, unfamiliar surroundings, and in some cases, an association of pain with all of these variables if past visits to the office have resulted in surgical procedures. Another factor that has not been discussed is the ability of the dog or cat to sense that the owner or those around him are fearful, anxious, confident or defensive. The ability of an animal to sense the attitude and demeanor of those around him comes from the animal’s ancestral past. The wolf pack origins of the dog used these senses to determine the intentions of each of the members of the pack. If the owner is a member of the dogs pack, then the dog is able to sense the feelings of the owner. Generally speaking, “aggression at the veterinarian’s office is caused by fear”. (Schwartz) When the owner is not there and the animal is being cared for at the hospital, a continued awareness of the instinctual need of animals to control their environment and the propensity to defend themselves is paramount to being safe on the job.