Dogs bark and lunge toward other dogs when they cannot access the dog. Often, dogs with frustration-based aggression are friendly with dogs they meet without a barrier. Some people refer to this behavior as 'leash aggression' or even 'reactivity', though those terms do not specify the underlying motivation.
Teach Your Dog an Incompatible Alternative Behavior
For example, they can't lunge towards another dog and turn to look at you at the same time. If you heavily reward this alternative behavior, your dog will eventually choose to do it in place of lunging even when their trigger is close by.
Dogs that bark and lunge when they see another pooch approaching aren't always displaying frustrated greetings. More commonly, fear is the driving force behind reactivity. If something is making your dog uncomfortable, then being trapped on the leash can heighten their anxiety.
Dogs in the same household can become aggressive toward each other for a variety of different reasons. Aggression may be dominance-related, territorial, possessive, or caused by fear/anxiety. Some dogs have “alliance aggression”.
A reactive dog is usually a fearful dog. Causes can be genetic, but they are more likely due to a lack of socialization, prior bad experiences or a lack of training. Aggressive dogs show similar signs but are determined to cause harm and destruction.
Do not punish. Punishment won't help and, in fact, will make the problem worse. If the reactivity is motivated by fear, punishment will make your dog more fearful, and could lead to aggression.
Forgiveness brings stress relief.
Both tended to spend more time together after the conflict regardless of if they had an existing relationship. While it seems dogs do forgive after a fight, there's still a lot more to learn about reconciliation in dogs. In some multi-dog households, it doesn't always work out.
Don't Let the Dogs “Work It Out”
Years ago, people used to believe in letting dogs fight to work it out between them. This is dangerous for both dogs and for nearby people. Also, the dogs may never get along after such a fight.
In most cases, the best way to get a reactive dog ready for socializing is to slowly expose them to their triggers in a controlled environment and reward them with natural dog treats until they no longer react so strongly.
It's important to understand that there is no "cure" for dog aggression. However, with proper training and management, most dogs can learn to control their aggression and live peacefully with other dogs.
Dogs are inherently social animals that live well together in groups, but that does not mean that all dogs get along. Most dogs will welcome a new sibling, but it is not always smooth sailing.
Can dogs live together after fighting? The answer is, most of the time, YES. There are times when dogs may be like an incompatible couple and need to divorce, but in general, there are things you can do to help combative pups get along.
Some have recommended that the dogs not be anywhere near one another for at least 48 hours following the fight, even if they live in the same household, while others recommend that getting a positive interaction between the two animals as soon as possible is the best course of action -- at the end of the day, however, ...
In a real fight, the dogs will target the stomach, throat, and front legs and the victim of the attack will often retaliate by grabbing a hold of the other dog's neck. If your dog is involved in such a fight and receives severe injuries, take him to the vet immediately.
Dogs of any age can start training to improve their reactivity. You do need to keep in mind that the longer a behavior has been ingrained, the longer it will take to retrain the dog. Whether or not the dog will be “cured” in the sense of being completely fine in the presence of his triggers cannot be predicted.
This kind of work can take anywhere from two to 12 months, as that's how long it takes for a dog to learn a new behavior. After that time period, you should be able to substitute negative reactions with positive thoughts.
Tugging on the leash or keeping it too taut will only make a reactive dog feel more trapped. Creating a safe distance and using barriers are much more effective. Do not overload your dog. If your reactive dog is exposed to too many triggers in too short a period, they will likely feel overwhelmed and react.