It said “Spayed and Neutered Dogs Live Longer!”
So I went off to investigate.
A new study on over forty thousand spayed and neutered dogs has shown that they live on average a year and a half longer than their intact friends and relatives.
Forty thousand dogs! That is a huge study. The results must be indisputable right?
But before you rush off to separate your pal from his gonads, let’s give that study a closer look.
Because the two groups of dogs died from very different causes.
What did they die of?
The spayed and castrated dogs were more likely to die from auto-immune diseases and cancer. The average dog owner has little or no power to influence whether or not his neutered dog will suffer from these conditions.
The intact dogs on the other hand, were more likely to die from infectious diseases and trauma. Both largely preventable by responsible ownership.
One explanation for these statistics is that neutered dogs are less likely to roam as this behaviour is often triggered by a desire to find a sexual partner. Roaming puts dogs at higher risk of both infection, and accidents.
It is also possible that neutering in some way improves the dog’s ability to fight infectious diseases. We simply don’t know yet if this is the case.
There are some other factors worth noting
All hospital patients
It is worth pointing out that this study was carried out using records of dogs that had been presented as patients at a veterinary hospital. Dogs that had had no need of veterinary treatment, or that were never presented for veterinary treatment, were not included in this study.
An American study
The study was carried out in the USA where there is a widely held belief that neutering is the responsible pet owner’s duty. This could mean that the unaltered dogs in the study were not given the same level of care as those that had been neutered.
Again, we just don’t know.
Because there are so many variables, we cannot assume that the conclusions of the study can be applied to the wider population of domestic dogs. But it is certainly an interesting study to add to our growing pool of information on this important topic.
The neutered dogs in the study were more likely to suffer from cancer than the intact dogs, with the exception of mammary cancer. So it is reasonable to continue to assume that protection against mammary cancer can indeed be achieved by neutering at a relatively early stage in life.