When I was in veterinary school in the early 1980s, I adopted a dog named “Jake” from a friend. The dog was a very good-natured, handsome mixed breed about five years old. Thinking about him all these years later, I’m struck by the fact that Jake was unneutered, and I had no problem with that at the time. As I recall, it didn’t seem unusual back then to have an “intact” dog, and I don’t remember anyone making an issue over it either. Since then, however, attitudes here in the US concerning spaying and neutering dogs have completely changed.
These days, except for dog breeders, most people accept that all male dogs should be neutered and female dogs spayed. You can’t even adopt a dog from most animal shelters that isn’t already “fixed.” This change in attitude over the last 30 years has resulted in a dramatic reduction in the number of stray and unwanted dogs in the US, which is obviously a very good thing. Veterinarians like myself have assured our dog-owning clients that neutering and spaying is the responsible thing to do to avoid unwanted litters of puppies, as well as reducing some behavioral and medical problems. When it comes to what age puppies should be sterilized, the answer coming from most animal shelters has been ”as soon as possible.”
I have always been more comfortable waiting until a dog is at least six months old before spaying or neutering, but an article I read several years ago suggested that dogs who are sterilized prior to becoming fully physically mature have an increased incidence of injuries to the anterior cruciate ligament (ACL) of the knee. These injuries are so prevalent today in medium to large breed dogs, some veterinary orthopedic surgeons report that ACL injuries make up well over 50 percent of their caseloads. A study done at Cornell University showed an increase of hip dysplasia in dogs that were surgically altered at a young age. Even more concerning was a study done showing a significant increase in cases of bone cancer in Rottweilers altered before one year of age. Because of these issues, I began recommending people wait until their dogs are fully mature, even up to one year old before having them fixed.
More recent studies have shown significant links between spaying/neutering in dogs and behavioral problems, thyroid issues, and even increased incidence of several potentially fatal types of cancer. While it’s clear that routine altering of dogs will continue to be the standard for the foreseeable future, there are currently alternatives to conventional sterilization. When our Blue Heeler mix “Tica” was eight months old, for example, I surgically removed her uterus, but left her ovaries intact. She still comes into heat once a year or so, but she can’t get pregnant. All her natural hormones are present, which hopefully will help to avoid some potentially serious health issues in the future. Male dogs can have vasectomies which keep hormones intact but eliminates the ability to father a litter of pups. A more recent FDA approved non-surgical technique called “Zeutering” renders a male dogs sterile, but keeps some of the sex hormones intact.
Many people have been led to believe that neutering male dogs is essential to eliminating aggression and other unwanted territorial behaviours, but I have not found that to be necessarily true. I have quite a few intact dog patients at my clinic that are perfect gentlemen. I understand that many of my clients don’t want to deal with their female dogs coming into heat, even without the risk of pregnancy. I also understand that animal shelters have an imperative to reduce unwanted puppies In our communities. But knowing what I know now, I no longer recommend conventional altering for all my canine patients (cats are a different matter altogether), and instead suggest waiting until they are fully mature if they are to be spayed or neutered.
Dr Judkins is the owner of Animalkind Holistic Veterinary Clinic in Historic Jacksonville