Dogs get into scrapes with other dogs as a way of figuring out who's dominant to whom in canine society, to defend territory (including mating rights), out of fear, to protect their food, and sometimes as a defensive "first strike" when they encounter a dog who has attacked them in the past. A neutered or spayed dog who has spent his formative early weeks of life with his mom and littermates and has had plenty of socialization since -- with other dogs and people, too -- has the best chance of staying out of fights. Of course, all that is water under the bridge once you have an adult dog who is a fighter. You might always have a fighting dog, but you can take steps to keep the situation under control.
Your reaction determines how your dog will react to other dogs. If you anticipate trouble when you see other dogs headed your way, your dog will pick up on your uneasiness and immediately perceive the approaching dog as a threat. Keep a loose lead, keep moving, and keep up a happy stream of conversation. Your dog needs to learn to view the approach of other dogs as normal, not negative.
Every dog, especially one who's prone to fighting, should be obedience trained. When another dog approaches, require your dog to go through an obedience routine or perform some other activity to take his attention off the other dog and focus it on you. If he starts growling or barking at the new arrival, you can now legitimately correct him for failing to respond to commands, not because of the approach of another dog.
Reproduction is a driving force behind territorial and aggressive fighting. Neutering a male dog is an absolute must for controlling and correcting fighting. Female dogs can be aggressive, too, and spaying is just as important. In fact, neutering and spaying have significant, long-range health and behavior benefits for all dogs.
When to Call a Behaviorist
All dogs are not created equal, especially when it comes to dominance. If there's fighting between two dogs in your own household, they may be trying to figure out who answers to whom. A behaviorist can help you understand what's going on and offer advice on how to solve the problem. Remember, to a dog, being dominant or subordinate is a perfectly normal and natural thing. Don't make the mistake of thinking your dogs must treat each other as equals. Correcting dog behavior means occasionally thinking like a dog.
If your dog growls whenever you get close to one of his bones or food, it can be a real nuisance. In the next section, we'll learn how to cure your dog of excessive guarding.