To Neuter or Not To Neuter the Dog?

Resource guarding in dogs is not hopeless.

A little over a month ago, I agreed to foster a husky and Australian shepherd mix. This little blue-eyed beauty was filled with energy. When I took him in, he had not been neutered. I wasn’t concerned because, statistically, there isn’t much evidence to connect intact dogs with aggressive behavior and resource guarding.

I had always neutered and spayed my dogs, but primarily to prevent reckless breeding, although, for decades, I had ‘heard’ that intact dogs were more aggressive. Like so many things we hear over the years, they have a tendency to become facts over time despite a lack of evidence.

In addition to the foster, Timba, I had three resident dogs: Two Belgian Malinois, Axel and Tango, and a Golden Retriever, Piper. All three were rescues. I didn’t want another dog, at least not for long. Unfortunately, Timba had such an engaging personality I decided to keep him. I was officially a foster fail.

In consultation with my vet of many years, we decided to wait several months before neutering the 15-month-old Timba.

The main issue with Timba was his constant resource guarding. He would snarl and attack the other dogs over toys and treats, and one of them, Axel, resented this behavior. This was becoming a problem as this Malinois was high-strung and high-energy anyway, and introducing a new dog into the mix created an element of chaos.

I use crates for those times when I don’t need dogs underfoot, such as when I work out in the house. I didn’t want to trip over one of them and tumble into a TV or a dog. I found myself crating Axel and Timba more often than I would like, so I decided, after two weeks, to go ahead and neuter Timba. Despite the lack of evidence, old habits die hard, and I hoped that neutering would help mitigate resource guarding.

Within two weeks, Timba stopped guarding resources. His behavior also mellowed, and his aggression was non-existent. The exception was Axel. These two hate each other, so I keep them separated. At some point, I hope this aggression works itself out.

The bigger question is whether the neutering or just the passage of time had stopped the resource guarding. Much of this behavior is based on anxiety, and when new dogs are introduced to an existing pack, there is substantial anxiety. This is present in all dogs, so proper introductions and training are essential.

In conclusion, the presence of testosterone in dogs peaks at around ten months. Beyond that, little is understood about the role of testosterone in dogs. The National Institutes of Health offer the following:

Aggressive behavior in dogs poses public health and animal welfare concerns. However, the biological mechanisms regulating dog aggression are not well understood.

For example, in some studies, gonadectomy (which yields decreased androgen production) has been linked to a mild reduction in male dog aggression toward both other dogs and people (Neilson et al., 1997). In contrast, in others, neutered dogs were found to be more aggressive (Guy et al., 2001).

As you can see, the evidence for anything beyond a mild reduction in aggression following neutering is not particularly significant. So, that begs the question: does the simple passage of time and proper introductions reduce resource guarding?

This is a conundrum. Regardless, except for expenses, I don’t see the downside to neutering dogs. After all, beyond aggression, it will reduce sex drive, so if your dog gets loose, you don’t have to worry about him chasing your neighbor’s pregnant prize terrier. At least not with that telltale gleam in the eye.

In conclusion, I will continue to neuter male dogs if any are in my future. I also want to highlight the importance of understanding and training your dogs. One without the other can be an exercise in futility.

This article speaks to dog-on-dog aggression. It does not speak to dogs on human aggression. That is an entirely different topic.

References:

Aggression in Gonadectomized and Intact Dogs (2018). Frontiers in Veterinary Science.

Endogenous Oxytocin, Vasopressin, and Aggression in Domestic Dogs (2017). National Library of Medicine.