Many of the reservations that owners, often men, have about neutering their male dogs stem from the myths surrounding what neutering will mean for their pets, in terms of how the dog experiences life. And, to really get a good understanding of your dog in this regard, it's important not to project your own subconscious feelings and associations about life as a human, onto life as a dog.
If you're not breeding your dog, there is no good reason to not have him neutered. You will ensure he does not contract the canine equivalent of HIV, reduce his aggressiveness, make sure he doesn't roam as much, and minimize his chances of getting prostate problems, some forms of cancer, and testicular problems as he ages. Not only does this improve his quality of life, but it reduces potential pain, and your vet bills.
These are some common myths surrounding dog neutering:
* "My dog will be upset with me for not ever having a sexual experience" - No, he absolutely will not. Sexual drives in dogs are purely instinctual. They are not romantic, or emotional, either in the sense of being 'loving', or as serving an emotional or psychological need for the dog. Your dog does not keep a little black book or count the number of females he has shagged. He does not discuss his sexual prowess with other females or mates, nor joke around with his mates about the rump of a female dog. So, it is not a bonding process in his relationships with other dogs, neither is it an induction into his 'manhood'.
Scientific studies have shown that dogs do not act out any sexual behaviour unless they are stimulated by their own hormones in response to a female on heat. They have no 'need' to engage in sexual activity other than as a biological response to perpetuating the species. It does not concern their dog minds in everyday life otherwise. They do not fantasize about shagging other dogs, neither are they preoccupied with the subject.
So, no, your dog will not be upset by not having a sexual experience.
* "My dog will become wimpy and sad" - This is not true either. Neutering does not affect your dog's stamina, or strength. Neither does not having sex with other dogs increase his stamina and strength. They are completely unrelated. Stamina and strength are the functions of health. If your dog is not beset by instinctual hormones that have no other purpose than to perpetuate the species, it means his body can use its energy and resources for other things - including stamina and strength. Again, it's important not to project one's own values and judgments onto dogs. That is called anthropomorphism.
* "My dog will not a good watch-dog anymore" - Absolutely untrue. Think for a minute how good a watch dog your dog is going to be if he tries to get out all the time to catch the latest stray female on heat in the neighborhood. Taking into the myths above, we have established that your dog's strength and ability to be trained is not affected by neutering.
* "It is unnatural to neuter a male dog" - Given that the environment we raise our pets is completely unrelated to the natural environment, where they are dependent on people for their food, health and shelter, how is it possible to suddenly raise this point? And consider the way that HIV, and all the other changes we as humans have created within the dog's natural environment, the wild, have changed that environment to the point where many species who rely on this environment exclusively, are becoming extinct. It seems more than hypocritical to seriously believe you are doing something positive for your dog by entertaining this thought.
Neutering non breeding dogs is a part of responsible dog ownership. It is part of helping a dog fit into the unnatural world we introduced them to with domesticity. It's been a long time since the dogs your pet descended from were running around in the wild with the wolves - assuming the wild is still around in your area.
If you're concerned about your dog's happiness in this way, take him for long walks and swims and make sure he has plenty of exercise. That is giving him a far greater benefit and taste of the good things he experienced when he was a wild dog than leaving him unneutered.
* "Neutering will make my dog get fat and lazy" - Actually, what will make your dog fat and lazy is if you, his owner, don't take him for long walks, over feed him, and don't provide him with the opportunity to get enough exercise. The operation has absolutely nothing to do with it. Responsible dog ownership, on the other hand, has everything to do with whether your dog will get fat and lazy. If you're relying on your dog roaming around at night chasing stray female dogs on heat as his only form of exercise, then there is a problem, and it's not with the dog.