Dog Penis 101: Everything You Need To Know

The canine penis is one of the least understood dog appendages.

As a dog owner with a male pooch, you may want to study this integral part of your dog’s existence. This information will help you understand your dog a lot better from their specific health needs to strange habits you may have picked up on.

We are surprised to learn that a dog penis has a bone in it, is easily inflamed, and tightens itself inside the female dog vagina in a process known as “knotting”. Let’s start off with the more common facts.

19. The Dog’s Sexual Function Is Related To Their Psyche

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Believe it or not, dogs too suffer from performance anxiety as well as libido issues related to their psychological wellbeing.

If a dog is anxious or scared by stimuli in the environment, they are unlikely to develop an erection or even show interest in female dogs.

For this reason, breeders take extra care to ensure that the prized studs are kept safe, happy, and comfortable in every way.

18. Always Ready For Action

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Unlike their female counterparts, male dogs do not have heat cycles. This means that their penises and testicles are designed to be ready for copulation all year round.

As a dog owner with a male best bud, you need to take this into account as the last thing you want is for your pet to be running around impregnating any dog they come across.

This seemingly never-ending libido could also put them at risk of issues with other dogs in the neighborhood as the turf wars are often driven by innate sexual instincts.

17. Neutered Dogs Can Still Get Erections

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Neutering is the process of removing the testicles from a male dog. The main aim is to curb hormone-charged outbursts and behavior like urine marking, humping, and aggression towards strangers.

Contrary to popular belief, it does not affect the dog’s penis in terms of the ability to get an erection. This is because the structures within the penis itself are left intact. However, the dog’s libido is markedly reduced.

16. Dog Humping Is Not Always Sexual

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There is probably nothing as awkward to deal with as a dog owner as a dog humping in the presence of guests or out in public. The common belief in these cases is that the dog is doing it to release sexual tension by stimulating the penis area. However, this is not always the case.

Dog behavior specialists believe that it is more of a playful habit than anything outrageous and inappropriate.

15. A Little Discharge Every Now And Then Is Normal

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For the most part, our minds go to the scariest places whenever we see any discharge from our dogs.

To be fair, discharge from a dog’s penis is highly likely to indicate infections either genital or urinary. However, some discharge may be completely harmless.

This is the case with the collection of natural lubricant and normal dead cells that may be expelled occasionally. If the amounts are small and the discharge is odorless, you probably have nothing to worry about.

14. Penis Sniffing As A Way To Communicate

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Another major source of embarrassment as a dog owner is when your dog and another dog start sniffing each other’s privates. Again, do not worry about this being deviant sexual displays that need to be punished right away.

This is because dogs do this as a way to communicate with each other. It is also a way to essentially size each other up and identify scents they may come across later.

13. Penis Licking Could Be A Sign Of Irritation

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Dogs tend to lick parts of their bodies that may be the source of any type of discomfort. This includes the penis.

If you notice your dog licking their penis a lot, it could be because they are experiencing some pain or irritation. It could be a result of trauma or even infections.

In such cases, it is best to keep an eye out for other signs and symptoms and get your dog to the vet.

12. There Are A Number Of Dog Penis Tumors

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A lot of dog breeds have cancer as the leading cause of death. These include gut tumors, skin cancer, and cancers in the reproductive system.

With the latter, penis tumors are a huge contributor to the statistics. They include squamous cell tumors, lymphomas, and papillomas. They also vary from hormonal to non-hormonal cancers that may occur even after spaying.

It is therefore very important to regularly have your dog checked so you can catch and treat the tumors early.

11. It Is Sometimes Referred To As The Dog Lipstick

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The dog penis is commonly known as the “dog’s lipstick”. This nickname is mainly due to the relationship between the appendage itself and the skin it hides behind.

When the dog gets excited, the penis grows erect and appears from behind the sack of skin like lipstick would from its case when twisted out.

It could also be due to the appearance of the penis itself both in terms of color and shape.

10. Erections Are Not Always Triggered By Arousal

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Your dog could and will most likely show their “lipstick” on the most inappropriate occasions. As previously discussed under humping and licking behavior, not all penis-related activities in a dog are sexual and their spontaneous erections are a fantastic example.

These could occur when the dog is simply happy and excited whether it is because their favorite human is back home or they received some praise after a successful training session.

9. The Penis Could Get Blocked By Stones

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Kidney and bladder stones are relatively common in dogs especially if they have renal issues or are simply not drinking enough water.

These usually have to pass out through the urethra that runs through the penis. With large stones, there is always the risk of developing blockage which could cause bleeding and intense pain.

So if you notice your dog is not peeing or if they do it comes out with blood, you need to book a vet trip.

8. Sometimes The Lipstick Refuses To Go Back In

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In some cases, the dog may not be able to retract its exposed penis. This is a condition known as paraphimosis.

This could be due to the overgrowth of skin and hair around the opening of the skin folds that hide the retracted penis. It could also be due to neurological issues or anatomic abnormalities.

If you notice this, you will have to take your pooch to the vet as soon as possible to prevent complications like urinary tract infections as well as permanent damage to the organ.

7. It Goes From Pink To Purple When Aroused

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When the dog is resting and unaroused, its penis will be pink to light red. However, as they get aroused and grows to erect the color changes to a darker shade of red that may even appear purplish.

This occurs due to the sudden rush of blood to the area that is required to get and keep the penis erect during coitus with a female dog.

6. Dogs Can Get And Transmit Canine STDs

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Believe it or not, human beings are not the only ones that can get sexually transmitted diseases.

Dogs can acquire these infections as well with male dogs often being mildly symptomatic or even asymptomatic carriers. In this case, the diseases are referred to as canine venereal diseases. The most common in this case is brucellosis.

If your dog goes outside unsupervised a lot, they are at a very high risk of getting and transmitting these diseases.

5. There Is A Sexually Transmissible Penis Tumor

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This STD is so interesting that it gets its spot on this list of interesting facts about the dog penis.

The disease is known as Canine Transmissible Venereal Tumor or CTVT for short. In male dogs, the tumor appears as a cauliflower-like growth on the shaft or the tip of the penis. However, it could be self-transferred to other parts of the body like adjacent skin and the snout.

4. It Carries The Urethra

As with any other male mammal, the urethra runs within the penis of a dog. It is protected by the baculum which we will mention again in a short while. This is meant to prevent trauma to the tube.

It is important to understand this relationship as it is the basis for interaction between urinary tract infections and canine venereal diseases. More often than not, they both manifest with changes in urinary patterns as well as discharge from the penis.

3. It Is Vulnerable To Infections And Inflammation

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The dog penis is hidden behind a stack of skin and fur which is often mistaken for the appendage itself.

However, this does not always protect it from things like an infection which can happen for several reasons. These include trauma, lacerations when they are humping, or even internal issues like complicated urinary tract infections.

You may notice tenderness, redness, and swelling around the area as well as smelly discharge.

2. Knotting During Coitus

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Knotting occurs when a male dog has penetrated a female dog just before ejaculation to inseminate the latter.

It happens when tissues in an erectile gland within the penis swell up and form a bulb. This effectively knots the male and female for several minutes to ensure that none of the sperm is wasted in the process. After a few minutes, the swelling reduces and the pair can disentangle and life moves on.

1. The Dog Penis Has A Bone Inside

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There is a bone in the penis of a dog known as a baculum. It is designed to maintain the dog’s erection even when they are not sexually excited.

This serves a scientific purpose by ensuring that copulation can go on for as long as possible to increase the chances of successful insemination and subsequent fertilization.

Unfortunately, this also increases the risk of fractures which can be greatly debilitating.

Can Dogs Get Sexually Transmitted Diseases (STDs)? 

Dogs can get sexually transmitted diseases which are specifically referred to as canine venereal diseases. These include brucellosis, canine herpes, and even a transmissible type of venereal tumor. It is therefore important to monitor mating behavior and consider spaying to reduce libido and chances of contracting STDs.

How Do You Know If Your Dog Has A Urinary Tract Infection (UTI)? 

The best way to know if your dog has a UTI is to monitor their urine output levels and frequency. More often than not, they will require more potty breaks than before and may even have pee accidents despite being trained. On the other hand, they may have no urine output at all in which case you should suspect major inflammation with blockage.

Can You Get An STD From A Dog Licking? 

If your skin is intact, you are not at risk of developing an STD from dog licking. There is also the fact that most of the germs responsible for canine venereal diseases only affect dogs. This means that even if they bite you, it is unlikely they will pass whatever they have to you.

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Pete Decker