It may be really difficult for you to imagine that the cuddly, adorable puppy living happily in your home and playing with your children could be a wolf in disguise displaying signs of aggression in certain circumstances. Unless you train your puppy correctly the possibility of aggression can quickly change to fact. It is best to gain control over this inappropriate behavior from an early age because the older your dog gets, the harder it will be to modify his character.
Your dog's natural instinct will be to protect his territory from strangers whether they are people or animals. This is perfectly normal but the way in which he protects your home needs to be dictated by you, not by him. When you are out walking with your dog observe his behavior toward other dogs. You will possibly notice that he won't attack larger dogs because he will recognize a threat to his own safety and respect the superiority of the other dog. If he encounters a dominant dog he may want to escape or roll over in a submissive position, particularly if he senses that the other dog is stronger or more intelligent than he is. This is an instinct which he has inherited from his wolf ancestry and just like wolves; the weaker of the two animals will back off to avoid a fight.
As humans, when we see a dog roll over onto its back we think that it just likes its belly rubbed. This is not the case - the dog is demonstrating that you are superior by assuming the submissive position. A balance needs to be achieved with this because if your dog automatically rolls over when he sees you or other dogs, he may have a very weak character. Building is confidence and strength is not easy but developing your relationship with him from a very early age is most important. He needs to understand that you are not his enemy but not to the point that he loses respect for you. Make sure that you are friends but maintain control because the least thing you want is for your dog to be overly submissive or dangerously aggressive.
Although some fights occur without warning, it is possible to recognize signals that dogs give out when there is likely to be confrontation. Staring, trying to mount another dog, growling or snarling and stiff movements are all signs of imminent danger. If your dog behaves in this way on sight of another dog first issue the command "No". You can also try this command on the other dog as it is approaching. If this does not work a citronella spray can be most effective and will not damage either dog. If, despite your attempts to prevent it, a fight ensues do not put yourself between the dogs because you may be injured. Maintain a firm grip on your dog's leash if he is on one, or if the fight is between two family pets try dragging one of the dogs back by his hind legs. If there is someone around to assist you this is always preferable. If you show fear the dogs will sense it and you could be bitten. There are a number of reasons why dogs fight. Usually male dogs fight to protect territory and attain dominance. Female dogs often fight for possession or to protect their puppies. Neutered dogs tend to be less aggressive so if you find your dog fighting with bitches that reject his sexual demands, this is one solution.