Sexually mature dogs who aren't neutered are full of frenzied hormones, and that manifests in numerous different ways, most of which aren't too wonderful. Unfixed dogs, for example, often behave aggressively with fellow male canines, and sometimes even with people. They also often try to break away from home to mate. Fortunately, neutering frequently minimizes these hormonal behavioral styles in pets.
Aggression in Unfixed Dogs
Dogs who haven't been neutered often act more aggressively and fiercely than their fixed buddies. This behavior generally stems from the drive to defend territory and assert social power and strength. Fighting over mating access to females is another common root of unneutered doggie aggression.
Neutering and Aggression
In many cases, neutering does reduce or completely do away with aggression in dogs. Without the strong influence of hormones, many male dogs simply don't feel the need to battle it out with other animals or prove their dominance. Neutering often makes for dogs who are calmer and more at ease in general, without their hormones molding their actions.
Although neutering surgery frequently decreases aggressive behaviors in many canines, there are never any guarantees. Dogs often maintain hormonal behaviors, especially if they had time to become habits. Also note that all aggression in dogs is not necessarily related to hormones and sexuality. Dogs sometimes behave aggressively with others due to completely different reasons, such as fear, frustration and physical pain.
Female Dogs and Aggression
Unfixed canine aggression isn't just for the boys, either. Spaying female dogs sometimes helps curb fierce and feisty patterns, as well. Dogs who are spayed not only tend to stop being aggressive around other canines, they also usually relax around people, as well. Just as with the males, unspayed female dogs act truculently for numerous hormonally-charged reasons, whether for keeping resources away from others or for winning over any "mating-ready" males.
Caution With Aggressive Dogs
Aggressive dogs not only can be serious perils to the people in your household, but also to themselves and to other pets -- not safe. In many cases, neutering can help get the problem under control. If it doesn't, however, the assistance of a professional in pet behavior is 100 percent necessary. Aggressive dogs can be extremely dangerous, and it's imperative to never try to independently fix the situation. Doing so by yourself is just too big of a safety hazard. Instead, leave the task in the hands of a professional.