Dogs will attack other dogs for a number of reasons, some of which are fear, defensiveness, possessiveness of you and other family members or pets, and lack of socialization. Aggression between dogs can result in injury to dogs and/or to the people trying to separate them.
It is not only strange dogs that cause a dog to attack – dogs in the same household can become aggressive toward each other and launch an attack for a number of different reasons. The hierarchy between the dogs in the home can change over time, for example when one pet passes away or another becomes more mature.
It can be dominance related (especially if a new dog is brought into the home), territorial when another dog is perceived to have entered another dog’s space and possessiveness over food or toys.
There are various forms of aggression and it does not necessarily result in actual attacks but can include mounting, blocking or standing over another dog, staring and vocalizing.
Some dogs that have a strong bond with their owners will show aggression when with their owners but are peaceful when they are alone. They fight to get the attention of their owners and will fight other dogs in the home if they greet the owner simultaneously.
Dogs that are not neutered or spayed may be driven to aggression by hormones. Males will be aggressive to other males and females can become aggressive during their heat cycles of if she is protecting her pups. If you are not a breeder of dogs it is strongly recommended that you neuter or spay your dogs as it lowers the chances of reproductive health problems and it is has been studied and determined that spayed/neutered dogs, on average, live longer, healthier and calmer lives. The males lose the urge to dominate other males etc.
Changes within a household can cause aggression, for example when a new dog is introduced to the home or a puppy matures into an adult and tries to take a more dominant role in the home.
If an older pet becomes unhealthy or one of the family members, either another dog or a family member, passes away it can cause the dynamics in the home to change.
Our behaviour towards our dogs in our home can also contribute to any aggression, if we interfere in normal social behaviour or if we frequently yell at or scold our pets it may cause them to become anxious and respond negatively.
By not being consistent in our behaviour it causes confusion and uncertainty in the home. As pet owners we need to remain calm, show them that we are in control of any situation and that we are the “pack leader”.
Socialization is the most important part of your dogs’ life and the best way to avoid aggression in all its forms. It should be started when they are very young, by introducing them to other people and other animals so that it becomes a normal part of their lives.
A dog that is happy and healthy has no reason to be aggressive.
Most often a dog's aggression is motivated by fear, pain, illness, anxiety and not knowing what to expect and what to do in a situation that may arise. Our behaviour is vitally important to their well being and if you suspect an underlying reason for sudden aggression talk to your veterinarian and get advice on how to deal with this situation.