Does neutering a dog change his personality? Is it really necessary?

A good question for which everyone has a different answer. From anecdotes to scientific studies, the question of neutering raises some difficult questions. Yes, we all know that there are far too many puppies and kittens born every day — by some estimates, there are seven puppies and kittens born for every human in the United States. Such a rate leads to overcrowded pounds and large numbers of euthanizations.

Is neutering really necessary?

Neutering pets can help to decrease the countless puppies and kittens that are born without a home, but is neutering really necessary? What will be the consequences on our companions’ personalities?

There are many reasons that neutering dogs has become the norm in the United States. The advice of many veterinarians and common knowledge has taught us that hormones are the root cause of aggressive behavior in canines. Undesirable behaviors such as humping and roaming can also be attributed to sexual hormones.

The thinking behind such a widely accepted explanation is straightforward. Unfixed male dogs fight other other unfixed male dogs to prove their manliness, mark their territory, and show off for females. Humping your poor couch pillows, or worse, your leg, is a sign of uncontrollable sexual desire in a dog that has been disallowed to mate and is therefore frustrated. Wandering off and roaming again could stem from the desire to seek out new territory and searching for mates.

Dogs are not humans and do not perceive the world in the same way. Their simple minds will not miss their man bits, as their personality is primarily determined from environmental stimulation, anyway. And besides, doing the operation will protect the animal from dangerous cancers that could cost a lot of money to fight or worse, could result in the premature loss of your best friend.

Dog’s quality of life

But are you degrading your dog’s quality of life that it would have left? We’ve all heard anecdotes about dogs who lose their athleticism and their perkiness, begin gaining weight, and are no longer so interested in learning new frisbee tricks.  I decided to look into the question and found some interesting results.

While hormones do contribute to many of the undesirable behaviors that people neuter their dogs for, many of these behaviors are actually conditioned into a dog through practice, and fixing the dog will do almost nothing toward fixing the problem. Often, when a dog is well behaved, quiet, and blends into his environment, he is ignored. However, as soon as he begins humping your favorite pillow, he receives attention from his master.

Results of Studies

A couple studies have actually demonstrated that fixed dogs, male and female, display considerably more aggression than their intact counterparts, by as much as 30%! Further, neutered dogs also increased in fearfulness, touch sensitivity, and excitability. Therefore, according to these studies, neutering a dog results in more aggressive and fearful dogs that are more difficult to train. So much for conventional wisdom.

Further evidence that we may have the wrong idea about fixing dogs is that we are one of the only countries where the practice is so widespread. In Europe, neutering male dogs is actually the exception. In Sweden, nearly 99% of dogs are intact, and in Norway, it is actually against the law the neuter a dog except for medical reasons. It is no surprise that the Europeans view the United States neutering epidemics as another weird quirk from the far side of the pond.

Changes in dog personality and Health problems

So, will neutering a dog change his personality? What about all the orphan puppies and kittens born on the streets that end up in shelters? What about the health problems associated with keeping a dog intact, including pancreatic cancers?

The first is a legitimate concern. Ask any shelter volunteer. Our country does have a pet overpopulation problem. For that reason, I am inclined to believe that some shelter animals should probably be neutered. If they lived the lives that allowed them to end up on the street, it is quite possible they may end up there again. Without a stable home, one unfixed, stray male dog could impregnate many female dogs, homeless or otherwise. There may be some associated behavioral changes, but none that compare to the environmental trauma that the dogs has likely already experienced.

However, consider the flip of the coin. If a shelter animal’s aggressive behavior stems from fear, and if neutering a dog increases its aggression and fear responses, then neutering a shelter dog might make it completely unsuitable for adoption. Especially if the operation increases its already established behavior problems and makes training even more difficult.

As for the second concern of various cancers associated with leaving a dog unfixed… Do we “fix” human males in hopes that they might avoid the risk of a possible pancreatic cancer diagnosis later in life? If we know that neutering a dog might have negative influences on his behavior and potentially decrease his quality of life, is it worth taken many dog-years away from him to avoid the possibility of higher medical bills and maybe the loss of a little bit of time? Is a shorter life well lived worth a longer and more fearful one?