The Spay and Neuter Controversy
Spaying and neutering refers to the removal of a dog’s reproductive organs to prevent them from reproducing. Spaying and neutering is often encouraged by veterinarians, animal shelters, animal welfare organizations and other pet owners as responsible pet ownership to avoid bringing unwanted puppies into the world that might never find their forever home.
Proponents of spaying and neutering domestic pets also say that there are a number of additional benefits for pet owners and their pets, particularly that a spayed or neutered dog will experience fewer health problems down the road than a dog that was left intact (not spayed or neutered).
But what if you could make sure your intact (not spayed or neutered) dog never bred? Are the health benefits and positive behavioural effects of spaying/neutering significant?
Health effects of spaying and neutering
Spaying or neutering your dog has several health benefits, including a decrease in certain cancers. However, when you spay or neuter a dog, you are removing organs that produce hormones which have an effect on how a dog’s body works and grows if the procedure is done earlier in a dog’s life.
There is research that suggests neutered/spayed dogs may be at a health disadvantage in some areas as well, somewhat dependent on how early the dog is spayed/neutered. This UC Davis study from 2012 studied 759 Golden Retrievers, and had several different health-effect findings:
- Males neutered before one year old had double the chance of having hip dysplasia.
- Males neutered early were three times as likely to suffer from lymphosarcoma (a common malignant cancer in dogs) as intact dogs.
- Females spayed after one year were four times as likely to suffer from Hemangiosarcoma (a cancer common in dogs like Golden Retrievers) than dogs who were spayed earlier or not at all.
Just to make it more confusing, there are two additional studies that indicate neutered dogs were likely to live longer than intact dogs and specifically, female Rottweilers spayed after age 4 were more likely to live longer than the same type of dog spayed at an early age.
The debate on when to spay or neuter
The studies above indicate that the timing of spaying or neutering might alter the health effects. The American Humane Association recommends that spaying or neutering is done as early as eight weeks if possible. But some spay and neuter clinics, such as the Ontario SPCA Spay/Neuter Service, will only accept animals between four months and five years of age – far above the aforementioned eight weeks.
But how early, is too early?
Aside from the medical information gathered from the studies above, there are some arguments against neutering and spaying too early. For example, some veterinarians say that spaying and neutering too early will deprive your dog of sex hormones that make it necessary for the animal to mature fully. In addition, these same hormones are responsible for the animal’s skeletal growth and when animals are spayed or neutered earlier it may take much longer for their growth plates to close, while their long bones will grow a bit more than dogs who weren’t fixed as early.
Proponents of early neutering (prepubertal neutering, before a dog or cat goes through “puberty”) say that all of the evidence points to prepubertal neutering being the best option for pets. According to veterinarian Dr. Jeff Young in his article The Controversy is Over: Prepubertal Neutering is the Surgery of Choice, there isn’t any specific medical reason why most veterinarians recommend spaying and neutering between six and eight months, instead, it’s simply tradition.
Dr. Young also says in his article that there isn’t any evidence that a slower closing of growth plates, which can happen in animals that are spayed or neutered early, can be detrimental to the animal.
The behavioural effects from neutering or spaying are generally thought to be for the positive. This is because the primary behavioural effect of neutering or spaying an animal removes its drive to find a mate, which can reduce their likelihood of escaping or roaming as well as any aggression towards their “competition”, especially in males. Spaying female dogs can also eliminate the “messiness” associated with heats. Mounting, wandering, certain aggressions and marking are all behaviours that may or may not be fixed by spaying or neutering, depending on the dog and how they’re raised.
There are studies that indicate early neutering can be associated with even more mounting or noise phobias, fearful behaviour and increased reactivity.
It’s clear from the fact that there are so many different studies and opinions that we don’t know as much about spaying/neutering or leaving dogs intact as we think we do, and it’s difficult to default to the argument that leaving a dog “intact” is natural when we consider that domestic dogs have been selectively bred for centuries, often leading to predispositions and health problems that would not exist otherwise.
Are your pets spayed or neutered? Why or why not? Will you spay or neuter any future pets?