Canine Rivalry
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What Is Canine Rivalry?
Canine rivalry refers to repeated conflicts between dogs living in the same household. Animals that live in social groups establish a social structure within the group called a dominance hierarchy. This dominance hierarchy normally serves to maintain order, reduce conflict and promote cooperation among group members. Conflicts arise between household dogs when there is instability in the hierarchy, that is, when the ranking or social position of each dog is not clear or is in contention. Initially, dogs may only snarl, growl or snap without injuring each other. Sometimes, however, the conflict may intensify into prolonged bouts of dangerous fighting which may result in one or both dogs being injured.

Getting Professional Help
Ongoing canine rivalry is potentially dangerous since the dogs could be severely injured, as well as family members, if they become the object of redirected aggression when the dogs are fighting. Because resolving rivalry problems requires managing the dogs' somewhat complex social behaviors, it's often necessary for owners to obtain assistance from a professional animal behaviorist (see our handout: "A Guide to Finding Professional Help for Animal Behavior Problems"). Animal behaviorists are trained to observe, interpret and modify animal behavior.

Why Conflict Occurs
Conflicts* between household dogs usually develop when the ranking of each dog is not clear or is in contention. This may occur if:

• You attempt to treat both dogs equally, rather than supporting the dominant dog's position.
• You interrupt or interfere with the dominant dog's ability to control the preferred items (food, toys, beds, attention) in his environment by giving preferential treatment to the subordinate dog(s).
• You prevent the dogs from expressing the signals and ritualized behaviors that establish dominance.
• A new animal has been introduced into the house.
• A resident animal has died or no longer lives in the house.
• A resident animal is re-introduced after an absence.
• A young, subordinate dog reaches social maturity (usually between ten months and two years of age).
• A dominant dog ages and cannot maintain his dominant status.

• Determining which dog is dominant: Individual personality, as well as breed characteristics, are important factors. The dog that demands to be fed first, petted first and through the door first is usually the dominant dog. Remember that the rankings may be different in different contexts (one dog may control food, while another may control resting places) and they may change over time.
• How dominance is established: Dogs usually establish their dominance hierarchies through a series of ritualized behaviors that include body postures and vocalizations that don't result in injury. One dog may "stand over" another by placing his paws or neck on the shoulders of the other. However, because of past experiences, inadequate socialization or genetic temperament tendencies some dogs may, with very little warning, escalate dominance displays into aggression. If this occurs, call our Behavior Helpline at 314-951-1540 or your veterinarian for a referral to a professional animal behaviorist.

• If the dogs involved are intact males or females, spay or neuter both dogs.
• Determine each dog's dominance status relative to each other. Remember that this ranking is based on the behavior of the dogs, and not what ranking you prefer.
• Support the dominance hierarchy. You need to support whatever dominance hierarchy or "pecking order" your dogs establish for themselves. Don't undermine their hierarchy by attempting to treat them equally or by preventing the dominant dog from asserting his position. Dominant dogs can, and should, be allowed to take toys away from subordinate dogs, to push in to receive attention and petting from the owner, to control favorite sleeping places, toys and other valuable resources (from the dogs' point of view). Support the dominant dog's status by allowing this to occur.
• Make sure that all of the humans in your household occupy the top of the dominance hierarchy by practicing "Nothing in Life is Free" (see our handout: "Nothing in Life is Free"). This provides stability at the top of the dominance hierarchy, which will help the dogs sort out their lower places in the pecking order more peacefully.
• Never, under any circumstances, attempt to break up a fight between dogs by grabbing their collars or inserting any of your body parts between them. If you feel you must break up a fight between dogs, do so by squirting them with a hose (outdoors), or squirting them with a vinegar/water mixture from a squirt bottle (indoors).
• With the help of a professional animal behaviorist, elicit and reinforce non-aggressive behaviors using counter conditioning and desensitization techniques. These procedures must be designed and tailored to specifically meet the needs of each individual case and require professional in-home help.
• You should be aware that if you respond to this type of problem inappropriately, you run the risk of intensifying the problem and potentially causing injury to yourself, your dogs or both.

Punishment Will Not Solve The Problem
Punishment can actually make the problem worse. We encourage you to seek assistance from your veterinarian regarding: spaying and neutering your pet; evaluating the health status of your dogs; for a referral to a professional animal behaviorist. Rivalry and fighting problems can usually be resolved so that you and your dogs can live together in peace.

If you would like further assistance with this, or another pet behavior topic, please contact our Behavior Helpline at (314) 951-1540 or e-mail behavior.desk@hsmo.org.
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