In Northern America, dogs are routinely spayed or neutered when they’re between 4 and 9 months old to prevent unwanted puppies. In Europe, they are spayed or neutered slightly later and because they allegedly “behave better”.
Well, you as a responsible dog owner know that both reasons are myths. You know what it takes to avoid unwanted puppies, like the alpha couple in a wolf pack, that prevents other pack members from mating. Naturally you will not leave your female in heat unsupervised in the back yard, and only walk her on-leash, and in areas that are not frequented by other dogs.
In my opinion every vet who spays/neuters a healthy dog younger than 20 months is simply greedy for money, because I don’t want to believe that he/she has not learnt about the latest scientific studies. Removing a dog’s ability to produce important hormones while his skeleton is still developing can result in delayed closure of the growth plates at the end of each long bone, which may put the dog at a higher risk for orthopedic disease, developing one or more joint disorders respectively.
Secondly, every event regarding health, and occurring before the age of 16 months may have a negative influence on the dog’s future behaviour.
However, even when we factor out the points above, and have a properly socialized, trained and therefore mannered adult dog that does not get a chance to mate, there may arise health reasons that suggest to help our dog with a surgery: Sterilization without desexing.
This means performing a procedure that will prevent pregnancy while sparing the testicles or ovaries so they can continue to produce hormones essential for the dog’s health and well-being. This typically involves a vasectomy for male dogs, and for females either a tubal ligation or a hysterectomy while preserving the hormone-producing ovaries. It also eliminates the possibility of pyometra because the uterus is removed.
For further information please consult the following links:
Dr. Robert Foley and Dr. Michael Ferber
For the ones that torture their dogs, because they don’t want to deal with the female blood or the male drops; don’t get a dog!
Hilsbos Dog Training in English 