Should we be Neutering Male Dogs for Behavioural Reasons?

Another fascinating study on the pros and cons of decision-making in neutering male dogs to help with behaviour problems. This comes from our Dutch colleagues. This is a brief summary…

Should we be neutering male dogs for behavioural reasons?



This was an online survey where dog owners were invited to fill in a questionnaire about their dogs and neutering. The completed questionnaires of 491 owners were used to collate the data. Most were women (89%), ranging in age from <35 years to >54 years). Most had completed higher professional education (52%) with vocational education above high school level (33%) and below this level (15%).


Regarding where owners sought behavioural advice – they asked veterinarian practitioners (72%), behavioural trainers (48%) and behavioural therapists (38%).

Regarding the question – in general, do you think that castrating dogs with behaviour would be helpful?

Overall, most owners disagreed (45%), compared to those that agreed (9%).

BUT … this trend was higher in owners with intact dogs (51% agreed, 8% disagreed), than for owners with castrated dogs was (38% disagreed, 12% agreed).

The owners who had their dog castrated for reasons of correcting its behaviour (9 categories of behaviour problems were listed in the questionnaire) were mostly satisfied with how castration had affected the behaviour(s) of concern.

BUT … of those only 32% said it helped with their own dog’s aggression, 51% said it made no difference, 18% said the dog’s aggression increased.

For an explanation of this, see TAKE HOME message below.



There was an apparent disconnect in the data collected when comparing the opinions of owners on the positive benefits of castration on male dogs in general, compared to the opinions of the owners who had had their dogs castrated for behaviour problems.

In short, there was a mis-match in the responses of owners who had had their own dog castrated (i.e. had invested in the idea) and their responses for dogs in general.

Practically, what this means is that – if a dog owner with a problem dog asks their doggie friends for advice on neutering, those friends who have had their own male dog neutered for a behaviour problem are more likely to recommend it, even if if id didn’t work for their own dog!

This is cognitive dissonance – a type of ‘post-purchase bias’ where we justify our decision to buy something, or invest in an idea, even if subsequent evidence suggests we’re wrong.


Owners asked for advice on castration mostly from Veterinarian practitioners.

But the authors of this report are concerned that vets are first and foremost trained in clinical medicine. They suggest that this is likely to make vets vulnerable to the Dunning Kruger Effect, which would arise where vets lack of knowledge on canine behaviour could lead them to not be aware of what they did’t know.

A lack of knowledge about a subject does lead us humans to over-estimate our competence in that subject, UNLESS we work hard to resist it.

In short, unless they have specific training and qualifications in canine behaviour, they are perhaps not the best professionals to help owners seeking advice about castrating their dogs for behaviour problems.

Dog owners are better advised to speak to a qualified canine behaviourist.

For more information on the Dunning Kruger Effect, CLICK HERE


Self-selecting online recruitment of dog owners biased towards females (89%), whose use of social media differs from that of men.
This may have skewed the responses to the questions.


You’re welcome! ? ? ?


© copyright Robert Falconer-Taylor, 2020

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Self-reports of Dutch dog owners on received professional advice, their opinions on castration and behavioural reasons for castrating male dogs
Pascalle E. M. Roulaux ,Ineke R. van Herwijnen,Bonne Beerda
Published: June 22, 2020