Why Are My Dog’s Balls Black?

Photo by Marcela on Flickr

As a responsible dog owner it’s your job to keep an eye on your pet’s health, even if this includes keeping an eye on his balls.

The moment you discover any change down there you need to make sure there’s nothing to worry about.

One of the most common questions pet parents have is why are my dog’s balls black?

There are many reasons why your dog’s scrotum gets darker, and we’ll look into them, but the short answer is that it’s most probably nothing serious.

What you will learn from this article:

  1. What do healthy dog balls look like?
  2. Why are my dog’s balls suddenly black?
  3. Why are my dog balls peeling?
  4. Black balls after neutering
  5. Why are my dog’s balls red?
  6. Does cancer cause black balls in dogs?
  7. Why does a neutered dog appear to have swollen balls when excited?
  8. Closing Thoughts

What do healthy dog balls look like?

To understand if there is a problem with your dog, first we need to consider how healthy dog balls look like.

The color of the scrotum, the little pouch that holds a dog’s testicles, is different from one animal to another.

As a general rule, the scrotum should be greyish in color.

However, the color depends on the level of skin pigmentation in the area. If your dog’s underbelly skin is rather dark, so will the scrotum be.

Many puppies present pinkish spots on the balls and that’s perfectly natural, as well.

As a pet owner, you are probably aware of the color of your dog’s balls, it’s your job after all, so you’ll notice if there’s anything different.

Now let’s see what a color change in your dog’s privates might mean.

Why are my dog’s balls suddenly black?


The most common reason why a dog’s scrotum gets darker in color is age.

As a dog matures, skin pigmentation levels increase and it’s perfectly normal that at some point his balls will become black. However, this is a gradual thing. 

You may be excused for not checking your dog’s balls every single day, who does that?

But then one day, when the dog gets on his back waiting for you scratch his belly you realize his balls turned black and you freak out.

Chances are it did not happen overnight, it’s not that they suddenly turned black, it’s just you weren’t paying attention.

As the dog matures, you might also notice black spots on his testicles, possibly many little spots or just a couple of large ones. 

Either way, this is just another sign of changes in pigmentation levels and totally normal.


On the other hand, if it is a sudden change in color, you should check out his scrotal area carefully and monitor his behavior.

When the dog’s balls suddenly become dark blue or black, this might indicate some sort of bruising.

Look for signs of scrapes, cuts or punctures as the dog might have injured himself while playing or chasing other animals.

Try to feel the balls gently and see if there’s any sign the dog is in pain.

If it looks like the dog hurt himself, you should see a vet, just to be sure it’s nothing serious.

However, if the balls don’t appear to be bothering him and he’s in no pain, give it a day or two to see what happens.

Maybe the bruising will disappear and the scrotum will get back to its usual color.

Why are my dog balls peeling?

In many cases, when a dog’s balls turn black, owners also notice the skin peeling in the area. This is usually the case when the dog has a skin irritation.

Most often the skin on his scrotum becomes too dry and starts peeling.

A tell-tale sign of a skin problem is the dog obsessively licking his privates in an effort to soothe the itch that is associated with dry skin.

Unfortunately, licking only provides temporary relief and the skin will become even more irritated.

If, upon examination, you come to the conclusion that he has a dry skin issue you can try to cure that by applying coconut oil or Vaseline.

Both are non-toxic to dogs even if they lick most of it off, but oily substances can resolve the dry skin issue by locking moisture in.

Black balls after neutering

A lot of pet owners complain their dog’s balls appear swollen and black after neutering.

Even if the incision to remove the dog’s testicles is small, it’s still a cut and that means damage to a skin that’s already very sensitive.

If the dog’s scrotum appears very dark in color during the first few days after neutering, that’s probably nothing to worry about. Instead, watch out for any redness that might indicate an infection.

If the vet fitted your dog with a cone, make sure he wears it so he cannot lick his by now missing balls.

Also, some sort of swelling is to be expected for a couple of days.

After that, the empty sack will become flat against the dog’s skin. If the swelling doesn’t go away in a few days and the dog appears feverish (check his nose!), he might have developed an infection, although such complications post-neutering are rare.

Why are my dog’s balls red?

If black balls are not a reason for concern, when you notice your dog’s scrotum is red you should take it seriously. When the dog’s balls turn red it’s a sign of inflammation and infection. The infection might be caused by an injury or by a problem with the balls themselves, if the dog is intact.

For instance, it might be that the dog has a bladder infection and it’s spreading. See if the dog pees more often or seems to have trouble urinating. It’s best to see a vet rather than try to treat the infection yourself.

One of the most common causes of red balls is testicular torsion, which is not only extremely painful, but also dangerous. In testicular torsion, one or both balls become twisted and this impedes regular blood flow in the area. The balls also look swollen and tender to the touch.

If you suspect a testicular torsion you should head for the vet right away. The most important thing is to determine the causes, which might be trauma to the scrotum or an infection called brucellosis.

Many other types of bacterial or fungal infections can also cause testicular torsion. Your dog will have to be put on antibiotics, while packs of ice are applied to the region to reduce swelling.

In some cases, when just one of the testicles is affected, the doctor might recommend removing it before the infection spreads to the other one.

Does cancer cause black balls in dogs?

When they see their dog’s balls turning black, many pet owners wonder if this might be a sign of testicular cancer. However, hyperpigmentation is only one of the possible signs. Other early symptoms of testicular cancer include: asymmetric testicles, penile atrophy, swelling of the prepuce, hair loss or brittle hair, or changes in the dog urinates, squatting instead of raising a leg.

If your dog is intact, you should perform regular check ups on his testicles. It’s not only swelling you should be looking for, but a change in the way they feel to the touch. Sorry, you need to take care of this as the dog cannot tell you if something feels odd.

Normally, the dog’s ball should be soft, just like a firm grape. If you notice one or both feel harder, that might be a sign of cancer and you should go to the vet for an expert opinion. Also, the affected testicle might be a bit swollen, while the non-cancerous one starts shrinking.

Following a cancer diagnosis, the doctor will recommend immediate castration of the dog,  which solves the problem in 80-90% of the cases. Only if the cancer has metastasized the dog will have to have chemotherapy or radiation therapy.

Why does a neutered dog appear to have swollen balls when excited?

A neutered dog has lost his testicles so there’s nothing to get swollen in that empty sack. However, castrated dogs can still get excited, not necessarily in a sexual way, and then the mysterious bulbus glandis will get swollen. Contrary to the name, bulbus glandis, which is located at the base of the penis, is not a gland, but an erectile tissue structure involved in mating.  When the dog gets excited this bulbus glandis becomes apparent in the form of two swollen bumps on either side of the penis, and since they’re pretty close to the scrotum this might confuse the dog’s owner.   

And, since we’re there, neutered dogs can still have sex. They lose much of the urge after neutering, but it can occasionally happen that the dog will get aroused when meeting a female in heat. 

However, the bulbus glandis might become apparent even if the dog is just really excited to see you and he only wants a totally innocent belly rub.

Closing Thoughts

If you’ve just discovered that your dog’s balls have turned black, there’s no cause for alarm. In most cases, the change in color is caused by higher skin pigmentation levels, which are quite normal in an adult dog. Still, if the skin on his scrotum is peeling and the dog is licking himself like crazy he might have a skin condition. You can try applying coconut oil or Vaseline, and if  the condition doesn’t get any better you should see a vet.

However, if the dog’s balls look red, he might have an infection and that needs to be checked out as soon as possible.