As a dog owner, you will have noticed that your canine has many nipples along their underside, running from their groin all the way up to their torso. Perhaps your pooch has more or fewer nipples than other dogs, and this has left you wondering what is normal, or what it could mean for pregnant females. Thankfully this is no cause for concern, as some dogs can have an odd or even number of nipples.
Dogs have around 8 to 10 nipples, and it is not unheard of for the amount of nipples to range between 6 and 12. Dogs have this many to accommodate their large litters.
The number of nipples a dog has is similar for both large and small breeds, but because large breeds tend to have bigger litters, it is more likely that they will have more nipples to accommodate their young. In this brief guide, we’ll also look at dog nipple health, (particularly in females) and how they change during heat and pregnancy.
How Many Nipples Does a Male Dog Have?
Male dogs have two rows of nipples along each side of their belly with 4 or 5 in each row. Smaller dogs may have only 6 or 8 nipples, whilst larger breeds might have 10 nipples in total. Having an odd number of nipples is perfectly normal, but what seems like an extra nipple could sometimes be a tick or in rare cases, a cancerous lump (more on breast cancer in dogs further down).
It’s good to familiarize yourself with your dog’s chest and abdomen and have them checked out by a vet if you’re concerned about the amount or appearance of their nipples in any way.
How Many Nipples Do Female Dogs Have?
Females typically have the same number of nipples as male dogs – around 8 to 10. Because gender makes no difference to the amount of nipples a dog has, you will not be able to tell the sex of a puppy based on their nipple count.
Will a Female Dog’s Nipples Get Bigger When in Heat?
Yes. Commonly when a female dog is in heat or ‘in season’, her body is preparing itself for breeding and the possibility of carrying a litter, and this causes her nipples to swell to a larger size than normal. Females are normally in heat twice a year and each heat cycle lasts between 10 days and 2 weeks.
Enlarged nipples can also be a sign of a false or ‘phantasm pregnancy’, a rare phenomenon in dogs that mimics all the usual pregnancy symptoms. If you’re concerned that your dog could be pregnant, observe how long the swelling lasts in her nipples. If this is a phantasm pregnancy symptom, the nipples should return to normal size a few weeks after her heat cycle has ended.
Stages of Dog Nipples During Pregnancy
- 2-4 weeks after breeding – In this early stage, a dog’s nipples will begin to appear raised and turn dark pink due to an increase in blood supply.
- 5-6 weeks after – By day 40, the dog’s mammary glands (where her milk is produced) begin to enlarge. Around this period, you may notice a small amount of clear discharge coming from the nipples.
- The nipples will continue to enlarge up until the time she gives birth (around 9 weeks after breeding). During the later stages of pregnancy, it is perfectly normal for the nipples to begin leaking milk.
If you notice your dog’s nipples leaking anything other than milk or a clear discharge, this needs urgent attention from your vet, as this could be a sign of Mastitis, which can sometimes lead to cancer of the mammary gland (more on mastitis later on).
How Long Does It Take for a Dog’s Nipples to Go Back to Normal After Puppies?
A mother’s nipples or teats will return to normal during her puppy’s weaning period, which should take about 1 week. By the time the puppies are 5 to 6 weeks old, they’ll begin to develop sharper teeth, during which time the mother will find nursing uncomfortable and her milk production begins to slow down.
At this point, her puppies will be gradually moving onto solid foods and her nipples will become less tender as the puppies suckle less frequently.
Can You Tell How Many Puppies a Dog Will Have By Their Nipples?
No, dogs are naturally born with an average of 8 to 10 nipples in order to feed their potential young, but the number of nipples they have is not always an indication of how many puppies they will produce.
The most accurate way to predict their litter size is with an ultrasound scan at around 25 days.
Can a Dog Have More Puppies Than Nipples?
Yes, it is possible for dogs to have, say, 10 puppies despite only having 6 or 8 nipples – this is what leads to puppies competing for the optimal feeding spot and pushing weaker siblings out to become the strongest in the litter.
Are Dog Nipples Symmetrical?
It depends. Veterinarian Dr. Nataya Chayasriwong of the Country Oaks Pet Hospital in California states that “most dogs are symmetrical, meaning they have an even number of nipples on both sides. Sometimes there are an odd number of nipples though.”
Interestingly if a dog has a set of 10 nipples, they will have a pair of five different nipple types – cranial thoracic and caudal thoracic nipples (located on the chest), inguinal nipples (found in the groin), and the caudal and cranial abdominal nipples (located on and near the abdomen).
How Does a Female Dog Get Mastitis?
Mastitis is a painful inflammation of the nipple and commonly occurs in female dogs when they are nursing, but it can also happen when they are pregnant. The nipples become inflamed due to an accumulation of milk in the glands or due to a bacterial infection. If the mastitis is due to the former, this can be treated with oral antibiotics as prescribed by your vet.
If the mastitis is down to a bacterial infection, this is normally because one or more teats have been handled roughly and tugged by nursing puppies, leading to inflammation and swelling. Once the teat’s skin tissue has been torn, bacteria can enter the mammary gland and cause an infection, making nursing so painful for the mother that she is often reluctant to feed her litter.
Fortunately, there are ways of preventing mastitis in nursing dogs with the appropriate care, including:
- Bathing the mammary glands – keeping the teats cleaned regularly with frequent baths and wiping the ducts of excess milk is a key step in preventing infection and inflammation.
- Use a cabbage leaf compress – many dog owners swear by a cabbage leaf compress held against the affected mammary gland to bring down the pain and inflammation and help reduce the chances of infection. Secure a cold raw cabbage leaf to the area with a bandage and leave for several hours.
- Express milk yourself – if your dog’s puppies are not using all her teats equally, milk will accumulate in those ducts and swell. To avoid this pain and prevent the ducts from becoming too inflamed, express milk from her teats manually to ensure milk (and any bacteria) can drain equally from each gland.
Health Issues Associated with Male Nipples
Male dogs can also develop mastitis, so it’s important to look out for the symptoms. If your male dog’s nipples are swollen, there can be additional causes besides mastitis that range from mild irritations to more severe conditions:
- Irritation – This can be caused by rough play or abrasion from certain textures, causing the nipples to become inflamed, itchy, and larger in appearance.
- Anemia – Anemia reduces the red blood cell count in a dog’s body and diverts oxygen from the lungs to other parts of the body – like the nipples. A recent change in diet could lead to anemia which can present in subtle ways, such as swollen nipples.
- Testicular cancer – In rare cases, swollen nipples can be a sign that testicular cancer has spread to other parts of the body. However, this cancer is more likely to develop in older dogs (10 years plus).
- Mammary tumors – male dogs have a rare 1 percent risk of developing tumors in their mammary glands (nipples), but you should consult your vet if you notice symptoms such as lethargy, weight loss, growth on their abdomen, and bloody discharge from their nipples.
What Causes a Dog to Have Breast Cancer?
Sadly, 1 in 4 dogs will develop breast cancer (mammary tumors) and though the exact cause is still not fully understood, it is thought to be linked to the exposure to hormones such as progesterone and estrogen. These female hormones accelerate the growth of certain processes in the body, which causes mammary cells to multiply at a rapid rate.
Dogs are much more likely to be exposed to these hormones if they have not been neutered (spayed), which is why early spaying – preferably before their first heat cycle – can drastically reduce their risk of developing cancer.
Early spaying puts dogs at a 0.5% risk of developing breast cancer, whereas waiting until after their first or second heat can increase their cancer risk by up to 26%.