Instructions
Treat possible aggression in dogs by socializing them early. Dogs that are used to being around other dogs are more likely to not have issues of aggression. A socialized and obedient dog will not normally pick fights with other dogs. If another dog picks a fight with it, the trained dog will listen to its owner's command when called off.
Have your male dog neutered if it is having aggression issues. Chemicals from male hormones in dogs are the primary cause of aggression toward other male dogs. Neutering a male dog will help calm it down, and make it less aggressive towards other dogs.
Always keep an aggressive dog on a leash when in public around other dogs. This will ensure that he is under control when aggressive behavior sets in. Always discipline aggressive behavior with a sharp "no." Reward correct behavior with positive reinforcement. If a normally aggressive dog ignores the advances of another male dog, then he deserves a treat or a pat on the head for doing the right thing.
Stay calm and in control. Dogs can pick up on the feelings, fears and reactions of the humans around them. Do not think the worst when another male dog approaches; remaining calm will help your dog remain calm. Panic in a person will enhance panic in a dog, and can lead to aggression.
How to Handle Aggression With Two Male Dogs
Aggression between two male dogs can become a serious problem. Two male dogs will generally be aggressive with each other over a territory or food issue. Never step into the middle of a dog fight. This will cause serious injuries, as fighting dogs aren't thinking of who else they may hurt. It is important to deal with aggression in dogs immediately.