Aggression in Dogs – An Introduction

Aggression in dogs is divided into three types, dominance associated, fear associated and resource associated.  Aggression may also be associated with dogs who suffer from pain or anxiety.  For the next two weeks, my blogs will tackle this complex issue.  This post will introduce the types of aggression.  In the posts that follow, I will give general guidelines for treating each type.  Please remember, most dogs require a customized long-term treatment plan for a successful outcome.  Above all, be careful!  Take precautions to make sure everyone involved, including other pets in the family, are safe at all times.

1) Dominance based aggression – Some dogs are born with the desire to be in charge.  They start by dominating their littermates and work their way up the leadership ladder of the family as they mature.  These animals will try to dominate everyone in their family or pack including the humans.   In the end, they may even challenge the adults.  Alpha dominant dogs must be handled with the utmost caution.  Please note that the theory of dominance based aggression in dogs is largely based on studies of wolves which may or may not be true.  This theory which was taught when I was in veterinary school is now under debate. 

2) Fear based aggression – In my experience, fear is the most common cause of aggression in all kinds of animals.  The animal is frightened and bites to protect itself.  Usually, the animal will warn people to back off before attacking.  Fearful dogs will freeze in place, stop panting, refuse to eat, shake, cower, hide their head or urinate.  Unfortunately, people often miss or ignore these warning signs and receive a painful bite.  Fear may originate from a traumatic experience such as being attacked by another dog, learned from a family member or a side effect of anxiety. 
3) Resource guarding aggression – Dogs with this type of aggression guard things they consider important.  Food is the most common resource they protect but I know of dogs who guard beds, sofas, shady spots in the yard, toys and/or special companions.    

Although it’s not really a type of aggression, I always like to mention pain as a reason for biting and growling.  When a dog is painful, it will growl to warn people and other animals to leave them alone.  This is especially common in older patients who suffer from osteoarthritis.  Please contact your veterinarian to discuss any change in behavior. 

Published by kristennelsondvm

Dr. Kristen Nelson grew up on a farm in Watertown, Minn., where she developed a deep love for animals of all kinds. She received a Doctor of Veterinary Medicine degree from the University of Minnesota, College of Veterinary Medicine. Kris then completed a small-animal internship at the prestigious Animal Medical Center in New York City. In addition to writing and speaking, she cares for small and exotic animals in Scottsdale, Az. Dr. Nelson is widely quoted in the media. Her credits include Ladies’ Home Journal, USA TODAY, the Los Angeles Times and numerous radio and television interviews. Dr. Nelson has written two books, Coated With Fur: A Vet’s Life and Coated With Fur: A Blind Cat’s Love. Kris and her husband Steve share their home with rescued cats, birds and a dog.