I found this article on the internet not to long ago. It is VERY refreshing to see more and more people willing to take a close and objective look at the effects of this major surgery on their pets. And even more importantly, the more information available, the better informed decisions pet owners can make regarding the balance of their pets' health and well being and lifestyle with their own.
The Long-Term Health Effects of Spay / Neuter in Dogs by Laura Sanborn.
An objective reading of the veterinary medical literature reveals a complex
situation with respect to the longterm health impacts of spay/neuter in dogs.
The evidence shows that spay/neuter correlates with both positive AND adverse
health effects in dogs. It also suggests how much we really do not yet understand
about this subject.
On balance, it appears that no compelling case can be made for neutering most male dogs, especially immature male dogs, in order to prevent future health problems. The number of health problems associated with neutering may exceed the associated health benefits in most cases.