Updated: Dec 26, 2021
A famous Confucius quote says: “The beginning of wisdom is calling things by their real name”. Spaying and neutering are words that describe the surgical procedure commonly known as castration. We use words such as spaying or neutering because they have less shock value and they tend to reduce in our minds the negative implications of a term such as castration. However, if we want to be precise, if we want to truly understand a subject – especially one with severe medical implications – we must not choose the prettiest word, or the word that makes us feel most comfortable, but the word that is the most accurate. Only then we can begin to truly understand a subject and its implications and only then we can make wise decisions based on the facts.
Because of this, the term castration will be the term that we will use throughout this post. In this way a question such as “Should I consider spaying or neutering my pet early?” is more accurately asked like this: “Should I castrate my prepubescent pet?”. When veiled terms are used, our common sense is numbed but when we start calling things by their real name, our instincts and our judgment come together to work as they should in delivering the truth to us.
I'm sure that, while reading the words above, many of you have already felt an instinctual rejection of the idea of infant or teenage castration. Good! However, if we are to be wise, we should not base our decisions solely on our feelings unless those feelings are validated by hard facts and, if you keep reading, we will provide plenty of evidence that we hope will persuade you to wait until your puppy is fully developed before you rob him or her of vital hormones that are much needed for growth and for ensuring a long and healthy life.
We will not bore you with details but we will provide them to you and we strongly encourage you to research this matter before you make a decision.
Many vets promote prepubescent castration because they approach this subject thinking about the species as a whole and very often they lose focus of the individual. And who can blame them? If I would have to see hundreds of dogs abandoned, neglected, abused and euthanized and if I had to administer that final injection, my opinion on castration would probably shift away from the best interest of the puppy that I'm holding in my arms to the greater good for canines as a whole.
Therefore, I understand why the culture of early castration is so prevalent in the vet and rescue community but I have a responsibility to advocate for each individual puppy that I produce and I must insure that he or she gets the best chance at a healthy and happy life.
So, without further ado, here is a referenced list, of the supposed health benefits and proven side effects of early castration. I'm confident that, once the subject is properly researched, there is only one conclusion to be reached: castration best wait until the puppy is fully grown, around two years of age. Otherwise, castration must be done in a way that preserves the hormone producing organs. Those procedures are more complex but the option does exist.
Benefits of castration:
In females: prevents mammary cancer, eliminates uterine and ovarian cancer risk and prevents pyometra.
In males: prevents prostatic hypertrophy and eliminates testicular cancer risk as well as and certain types of hernias.
It also prevents unwanted breedings and it is said to change unwanted animal behaviors such as roaming and territorial aggression.
Side effects of early castration:
Cardiac tumors. Both sexes are at higher risk but particularly, castrated females are five times more likely to to suffer tumors of the heart than intact females.
Bone cancer. A twofold excess risk was observed among castrated dogs.
Moreover, the College of Veterinary Medicine at Michigan State University found that "castration at any age showed no sparing effect on the risk of development of prostate cancer in the dog."
Looking at cancer alone it gets pretty hard to appreciate the benefits of early castration. “I see your very slight chance of mammary cancer and raise you a certain increase in bone and heart tumors”. That is not a hand that you would ever choose to play.
2. Abnormal growth and bone development. Testosterone and estrogen play important roles in the development of muscles and bones. When we remove testosterone and estrogen during the puberty growth phase there will be consequences. That individual's height, muscle mass and bone formation will be greatly and negatively affected.
Taller. The earlier the castration. the taller the dog. Estrogen signals to the growth plates to stop. Therefore, if you remove the estrogen-producing organs in infant or teenage dogs, both female and male, you could expect growth plates to remain open and the dog to grow longer bones.
Preston Stubbs, DVM & Mark Bloomberg, DVM Seminars in Vet Med & Surgery, Small Animal, Volume 10, No 1 Feb 1995 Dept of Small Animal Clin Sci, Univ of Florida Katherine Salmeri, DVM, Mark Bllomber, DVM, Sherry Scuggs, BS, Victor Shille DVM, Journal of American Vet Med Association, Volume 198, No 7 1991
Cruciate rupture. Without estrogen to shut down growth, the growth will continue and produce abnormal growth patterns and bone structure resulting in irregular body proportions. "If the femur has achieved its genetically determined normal length at 8 months when a dog gets spayed or neutered, but the tibia, which normally stops growing at 12 to 14 months of age continues to grow, then an abnormal angle may develop at the stifle. In addition, with the extra growth, the lower leg below the stifle likely becomes heavier (because it is longer), and may cause increased stresses on the cranial cruciate ligament." - Chris Zink, DVM
Hip Dysplasia. Both male and female dogs castrated at an early age are more prone to hip dysplasia.
3. Hyperthyroidism. The removal of one organ puts pressure on another. Castrated dogs are more likely to develop hypothyroidism.
Panciera DL. Hypothyroidism in dogs: 66 cases (1987-1992). J Am Vet Med Assoc. 1994 Mar 1;204(5):761-7 Glickman L, N Glickman, and R Thorpe. The Golden Retriever Club of America National Health Survey, 1998-1999
4. Incontinence. Early castration increases the risk of urinary incontinence by up to 20%.
5. Wooly coat. There is no study to verify this as far as I know but based on anecdotal evidence from groomers, castrated dogs have very wooly coats, commonly called “spay coat”. It seems that castration stimulates overproduction of the undercoat but until more is known, this remains anecdotal.
Dr. Karen Becker is famous advocate for a wiser approach to castration. If you don't feel like reading too much on this subject or if you just don't have the time to put into extensive research then you can watch her video. It will paint a good picture of the subject and it will provide you with the information you need. Definitely worth the watch.
In conclusion, we do not advocate against castration. In particular for females, after a certain age and especially if they are not bred, the benefits do outweigh the risks. However, we do feel strongly about the fact that our puppies should be allowed to grow and develop fully before removing important hormones so crucial for their health.