How desexing can change male dog behaviour

desexing can change male dog behaviour
unneutered male dog behavior
Intact male dogs will often mark their territory – desexing helps to reduce this behaviour.

While desexing can change male dog behaviour, can it actually make aggression and barking worse? Are you thinking of getting your male dog de-sexed or neutered? Are you worried that this surgery might change your dog’s personality? Perhaps, you’ve heard that there are behavioural benefits to desexing male dogs.

Indeed, desexing does change a dog’s behaviour and, in most cases, the changes are positive. However, some behaviour research suggests that desexing a male dog too early can lead to an increase in aggression and fearfulness. Similarly, male dogs who kept their testicles for a longer period of time were less likely to bark persistently when excited and to be less anxious and fearful of sudden or loud noises.

Although some changes in a male dog’s behaviour post-desexing are temporary, there could be some permanent behavioural changes as well. Therefore when a dog trainer insists that you should desex your male dog to improve their behaviour; it’s important to consider the pros and cons of how desexing and when it’s done, can influence behaviour.

So, what can you expect, as a dog owner, after getting your male puppy desexed? 

This article covers all the changes you can expect in your male dog’s attitude after getting him neutered.

How desexing can change male dog behaviour (The Short Answer)

will desexing male dog calm him down
Intact male dogs can be aggressive towards other male dogs. This is particularly common in certain dog breeds like Dobermanns, Rottweilers, Staffordshire Bull Terriers etc.

Male dogs undergo several behavioural changes after their desexing surgery. Some become aggressive, depressed, anxious, and clingy right after being neutered. However, these changes are temporary and usually go away within a few weeks. But desexing can change male dog behaviour permanently causing a reduced tendency to run away, a lesser propensity to hump objects and other dogs, and reduced sporadic urination.

What are the Behavioural Effects of Neutering Your Male Dog? (The Details)

According to veterinary experts, desexing can change male dog behaviour, here are some changes you might expect in your male dog after having it ‘fixed’:

Temporary Behavioural Changes Right After the Surgery

pros and cons of desexing male dogs
Male dogs will often still lift their legs after desexing, but their tendency to scent mark everything in their immediate environment will be reduced.

Young male dogs going through adolescence are very active in the sexual arena while growing up if they are not neutered. Immediately after the neutering surgery, your dog might become moody for a few days. This can range from signs like reduced appetite, slight aggression, clinginess, hyper-arousal, increased fearfulness, depression or anxiety symptoms.

While desexing can change male dog behaviour permanently, these behavioural changes are only mild and temporary. They occur due to a spike in hormones after the desexing surgery. Soon your dog will be playing happily as normal.

In fact; in most cases, desexing can change male dog behaviour for the better with dogs becoming calmer and happier after the neutering surgery as their hormones settle.

Mood Changes – How desexing can change male dog behaviour

does desexing calm a male dog
Research has shown that early desexing of intact male dogs can increase aggression and fearfulness.

One of the biggest advantages of getting your male dog desexed is a reduced risk of developing certain canine cancers.

As explained earlier, some temporary effects of desexing surgery include moodiness and some male dogs tend to get aggressive and display behaviours like growling, snapping, snarling, etc. These behaviours are usually seen right after the procedure and go away once the hormones stabilise and pain subsides.

Therefore, it is important that dog parents understand that the benefits of desexing far outweigh such minor mood swings in their pets, as they usually go away after a few weeks.

It is also worthwhile noting that some dog breeds are genetically wired to be more aggressive than others. Therefore, these dogs may be predisposed to aggression and violent tendencies in the first place irrespective of the surgery.

Less Likelihood of Running Away

desexing male dog benefits
Intact male dogs are more likely to try and escape if they sense a female dog in heat. This can increase their risk of getting hit by a car.

Desexing your male has a great advantage in that; it may protect your dog and keep him safe.

Desexing can change male dog behaviour such that, he has no desire to wander off in search of a mate and that can protect you from a lot of heartache and hassle that come with a male dog digging under the fence or trying to jump over it to dash into vehicular traffic.

Less Humping

It can be quite embarrassing watching your male dog humping objects like pillows, legs and other dogs. Thankfully, the desexing surgery can put a stop to those male dog behaviours.

Reduced Territory Marking and Indoor Soiling

behavioural benefits of desexing male dogs

Unfixed male dogs cannot help themselves and urinate sporadically to mark their territory. Often, this behaviour may be seen indoors as your dog tries to warn other male dogs to stay away from his territory.

Desexing can change male dog behaviour when it comes to peeing on everything, you should see a reduction in this type of behaviour and you will have less clean-up to deal with.

Reduced Energy and Increased Appetite

male dog desexing age
Some male dogs will put on weight when they are desexed.

According to experts, a neutered dog may eat more and sleep more. He may be at risk of putting on weight due to the reduced growth rate, lower energy needs, reduced basal metabolic rate, and increased appetite. 

Your vet might recommend switching your dog to lower-calorie dog food – but this will depend on your dog’s activity levels, age, breed/size, and overall health.

FAQ – How desexing can change male dog behaviour

How long after a dog is neutered does he calm down?

For most male dogs, it may take between 1-4 weeks for the hormones to settle down or completely leave the body. However, the life skill of calmness can be improved dramatically through calm dog training. Implementing a calmness protocol for your dog, ensures they receive sufficient rest, mental stimulation and rewards for calm behaviour.

Why do male dogs act differently after being neutered?

After having his testicles removed, a male dog’s testosterone levels decrease drastically. With this reduction in testosterone, owners sometimes observe reduced aggression (over the long run), reduced tendency to run away, and decreased territory marking.

Do dogs sleep more after being neutered?

Dogs may sleep more until the anaesthesia of the desexing surgery wears off. Worry not, your dog should be fine in a couple of days. If not, please call your vet’s office.

What age should you desex a male dog?

A dog behaviour study by McGreevy et al 2018, looked at the link between behavioural risks in male dogs and the amount of time they have their testicles. The earlier a dog was desexed, the less likely it was that 2 undesirable behaviours would occur (howling and scent marking). Therefore, the shorter the time that male dogs keep their testicles and resultantly experience a significant reduction in testosterone, the less likely these dogs were to howl when left alone and urinate indoors.
In contrast, owners who waited to desex their dogs were less likely to report them suffering from unwanted behaviours, particularly aggression and fear.
Therefore, although desexing a male dog early (before puberty) can reduce howling and scent marking, it can also introduce a range of other behaviour problems relating to aggression and fear.

Pros and cons of desexing male dogs – the benefits and disadvantages explained

Male dogs desexed at an early age (before or during puberty) can show reduced scent-marking behaviour. Similarly, dog behaviour studies have shown that dogs desexed at an early age are also less likely to howl when left alone compared to entire male dogs. However, these pros are offset mainly by the concerning side effects of early male dog desexing. Research has shown that male dogs desexed before puberty are at an increased risk of displaying aggressive and fearful behaviour problems.
Desexing male dogs can also prevent testicular cancer of the intact male dog.

Will desexing my male dog stop aggression?

male dog desexing aggression

Dog behaviour research conducted by Professor Paul McGreevy (Veterinarian and expert in learning theory and animal training) has shown that desexing a male puppy early in life (before they go through puberty from 4-12 months of age) can actually increase aggression and fearfulness. Many aggression-related behaviour problems in dogs stem from a lack of confidence and optimism. Removing the testicles and subsequently drastically reducing the dog’s exposure to testosterone can have a negative effect on the dog’s confidence, increasing aggressive outbursts.

Now you know how desexing can change male dog behaviour

training intact male dogs
We’ve seen how desexing can change male dog behaviour both positively and negatively. While there are behavioural benefits, it needs to be done at the right age and for the right reasons.

We hope this brief guide helps you understand and know exactly what to expect after desexing your male dog. Neutering is generally a safe process and when timed well, its benefits far outweigh its risks. 

Current research suggests that desexing too early can lead to an increased risk of a male dog developing behaviour problems such as aggression and persistent barking. And although male dog desexing can reduce the number of unwanted pregnancies in dogs and thus the number of dogs surrendered to shelters.

The negative effects that early desexing can have on male dogs’ behaviour need to be considered because reasons for surrender are often related to behavioural issues. If desexing is causing an increase in behaviour problems in male dogs, it might also be contributing to people surrendering their dogs due to these bad behaviours.

desexing male dog behaviour

If you desex your male dog at an appropriate age, you may expect some sharp changes in your dog’s personality but, over the long term, you should have a much calmer and happier dog.

If needed, please speak with a dog behaviourist or veterinary behaviourist to understand more about your pet’s behavioural changes – both before and after the surgery.

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2 Responses

  1. It’s nice that you mentioned how desexing could change a dog’s behavior positively in most cases. Our pet dog has behavioral problems, so I think we should have him desexed. But before we commit to it, I think we should ask the opinion of a veterinarian first.

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Hi! I’m Tres! I’m passionate about dog behaviour and training. My dog training methods are effective for all breeds and goals. I have trained dogs for protection, obedience, manners, loose leash walking, crate training and have solved common behaviour problems such as reactivity, barking, separation anxiety and more. Let’s connect, sign up to my free newsletter (above) for helpful tips and upcoming training events.
dog trainer Sydney

Hi! I’m Tres! I’m passionate about dog behaviour and training. My dog training methods are effective for all breeds and goals. I have trained dogs for protection, obedience, manners, loose leash walking, crate training and have solved common behaviour problems such as reactivity, barking, separation anxiety and more. Let’s connect, sign up to my free newsletter (above) for helpful tips and upcoming training events.
dog trainer Sydney

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