I recently had a conversation at the Dog Park with a man who did not want to neuter his dog because he could not see any issues, such as aggression to other dogs, and "he'd be in pain for a week".
I found this article online with some of the medical reason's to Neuter your dog:
Traditionally neutering is done around six months of age, because that is the age of puberty in dogs. It is healthiest if neutering takes place after a puppy received at least two of its vaccinations to provide best immunity for most puppy hood diseases. Contrary to popular belief, castration of a male dog does not “break his spirit”… worldwide, it is probably the most common routine surgery done in animal hospitals. Neutering does not promote any undesirable physical or emotional impact on the dog. Neutering operations remove the source of testosterone, which leads to problematic, and often life-threatening health issues, as wells as undesired behavioral problems.
Here are the MEDICAL REASONS; there are also many other good and valid reasons to neuter. Testosterone is a very powerful anabolic steroid with many short and long-term effects. Here is a list of some of the medical conditions influenced by the presence of Testosterone.
1) Prostate effects
2) Hernias – There are a number of hernias caused by Testosterone, they include: Scrotal hernias, inguinal hernias (in the groin), and perineal hernias (the area next to the tail). These hernias all require surgical correction. These hernias can be severe and life threatening especially if an organ becomes entrapped in the hernia.
3) Cancer – numerous cancers have been directly associated with testosterone, they include: Sertoli Cell tumors, Leydig Cell tumors, Perianal adenocarcinoma, Seminomas and interstitial cell tumors. Also Primary Prostatic Carcinoma, as above, all require surgery and some may also require Radiation and/or Chemotherapy as well.
4) Infections – Brucellosis is the worst, it has only slight chronic signs in the dog but causes abortion in the bitch. Balanoposthitis a chronic infection of the prepuce and penis, inside the sheath, this is the dog that is dripping droplets of pus from the opening of the prepuce (or sheath).
Most of the above conditions are preventable by neutering your dog. Every man who owns a dog should read this and consider if he wants to put his dog through this. It has been proven that neutered dogs live longer, healthier, and happier lives. We should not anthropomorphize. That is to attribute human emotions apply to them, a dog doesn’t care whether it has been fixed or not. For those who are worried about the cosmetics, there are prosthetic implants, Neuticles tm, which can be placed in the scrotum at the time of neutering
Contrary to popular belief, there are no medical, emotional or sociological reasons for a male dog to sire, or female birth “just one litter”. A misinformation and/or misguidance may lead one to believe that “having just one litter” is somehow good for the dog psychologically or medically. And the emotional or educational benefit to your children to experience the birth, and care taking of a litter of pups should be a very carefully analyzed proposition. Will your children accompany you to the animal shelter when you drop off those last six puppies you “just weren’t able to find homes for”? If you do choose to allow your dog or cat to have a litter, please be certain that there are committed pet caretakers waiting and wanting to provide a home for them. Don’t contribute to the pathetic destruction of tens of thousands of animals euthanized yearly in pounds and shelters. You do have the power and intelligence to make a difference.