By Ron Hines DVM PhD
The most common non-medical problem that dog owners ask about is aggression toward people and other dogs. There is enormous variation in aggressiveness or assertiveness among dogs. Experiences in puppyhood influence aggressiveness as adults but genetics also plays a key role in this problem. Owner temperament is also a very important factor. The size of the dog involved determines the seriousness of this problem. Toy dogs can be almost cute when they growl and posture but large dogs are quite dangerous.
The dynamics of dog bites is not well understood by the public. Few people realize that the dogs involved tend to be family pets and not strays. Also, more than two-thirds of dog bites happen to people who are acquainted with the dog. More than half the dog bites occur to the very young and the very old and almost half of all bites to children are on areas of the face.
To understand canine dysfunctional aggression you need to understand factors in play when the dog was a puppy.
Beginning at three weeks, when their eyes open, and lasting until fourteen weeks of age, puppies develop bonds and sensitivity to the people and animals in their life. If a puppy is not exposed to positive interaction with dogs during this period they may grow up without the skills they need to deal with other dogs. If they are not exposed to people in a positive way during this period they may never be comfortable with people.
The middle of this learning window (8 weeks) is the best time to purchase a puppy. Puppies brought to their new home at ten to twelve weeks of age may be more fearful and slower to bond with their new family. If the socialization process is delayed until the puppy is twelve weeks old or older the dog may never be relaxed or interactive with people or other dogs. This is particularly true if the puppy has a natural shyness and fearfulness or if it is very aggressive by nature. If you do accept a puppy of this age be sure that you and your children handle it frequently and gently and not scold or speak to it harshly to it.
A puppy’s teenage years begin with it is sixteen weeks old and end when the pup is twelve to sixteen month old. Near the end of this period a hormonal surge causes dogs become protective and territorial. Males begin to lift their leg to urinate and females enter their first heat period. This will be the time that a normal dog begins to bark at strangers and guard the family and your property. This is also the time that some dogs begin to show objectionable aggressive behavior.
Besides age at socialization, individual genetics and breed are major factors in determining aggression. Guard dogs such are bred to be more aggressive than the hunting and companion breeds. Hormones at play in intact male dogs and in females nursing puppies both increase aggressive behavior. Excessive punishment, teasing, chaining in the yard can all contribute to problem behavior. Too much undeserved praise also can confuse dogs and lead to frustration and aggression.
There are a number of types of aggression. The most common forms are dominant and territorial aggression. Some dogs show fearful, possessive or intra-sexual (male to male and female to female) aggression while others have a predatory form of this trait.