Nursing and weaning puppies cause significant changes to a female dog’s mammary system and nipples. During pregnancy, a dog’s nipples enlarge and swell in preparation for producing milk. After the puppies are weaned, the dog’s nipples gradually shrink and recede over time. However, in some cases, a dog’s nipples may not fully go away after nursing. This article discusses the anatomy and purpose of dog nipples, what happens before and after pregnancy, typical nipple changes after weaning, reasons nipples may disappear or persist, and how to care for a dog’s nipples post-weaning.
Anatomy of Dog Nipples
Nipples are located on the underside of both male and female dogs, extending in two rows from the chest to the groin area. According to the AKC, the number of nipples can vary by breed, most commonly ranging from 8 to 10 nipples https://www.akc.org/expert-advice/health/male-dogs-nipples/. They tend to appear as small bumps on the dog’s stomach, each containing a mammary gland. While male dogs have nipples, the mammary glands are not functional.
In female dogs, the nipples and mammary glands develop during puberty. Before a dog is pregnant or in heat, the nipples are small, flat and pink. They tend to be darker in color on dogs with darker coats. When a female dog is nursing, the mammary glands produce milk and the teats become round, long and pliable to allow the puppies to nurse https://www.petplace.com/article/dogs/pet-health/structure-and-function-of-the-mammary-system-in-dogs/. The nipples will enlarge and elongate during pregnancy and nursing.
Purpose of Nipples
Nipples have an important purpose for female dogs – they allow the production and release of milk to feed puppies. Mother dogs start producing milk from their mammary glands during pregnancy in preparation for nursing their young after birth. The mammary glands connect to the nipples, and the puppies suckle the nipples to get milk for nourishment and growth during the early weeks of their life.
According to the AKC, female dogs generally have between 8 to 10 nipples, with 5 pairs lined up bilaterally on the chest. The number can vary by breed, age, and genetics, but having multiple nipples allows a mother dog to nurse a whole litter of puppies at once (AKC).
While male dogs also have nipples, they do not serve any functional purpose. Since male dogs do not nurse puppies, their nipples do not develop mammary glands or produce milk. The male nipple structure remains basic and undeveloped.
Changes During Pregnancy
One of the most notable changes that occurs when a female dog becomes pregnant is enlargement and pigmentation changes in the nipples. According to South Seattle Veterinary Clinic, this change typically happens 2-3 weeks after conception as the dog’s body prepares for nursing puppies. The nipples will become larger, elongate and protrude more. They will also darken in color, becoming a dark pink, red or brown.
As explained by RexiPets, the darkening of the areolas and nipples occurs due to the increased blood flow to the mammary glands that happens during pregnancy. This helps the puppies locate the nipples once they are born. The texture of the nipples also changes, becoming firm and erect as they fill with colostrum in preparation for nursing.
These changes help prepare the female dog’s body for nursing and allow the puppies to easily find the milk source after birth. The nipples will continue to elongate and become more pigmented as the pregnancy progresses until whelping.
Nursing Puppies
Puppies rely on their mother’s milk as their sole source of nutrition for the first few weeks of life. They nurse frequently, stimulated by hormones from the mother dog. According to the Cornell University College of Veterinary Medicine, puppies nurse every 1-2 hours during the first week, tapering to four times a day by three to four weeks old. Sleeping time between feedings can last up to two hours initially, extending to four hours by three weeks old.
The nursing stimulation from puppies causes the mother dog’s mammary glands to produce milk. The first milk produced is called colostrum, which contains important antibodies to boost the puppies’ immune systems. After a few days, the mother’s milk transitions to provide complete nutrition for the puppies with the right balance of protein, fat, and carbohydrates. Nursing the puppies also prompts the mother dog’s uterus to contract, helping it return to normal size after pregnancy.
According to PetMD, puppies should nurse exclusively from their mother for the first 3-4 weeks of life. Around 3-4 weeks old, the mother dog may start limiting nursing time. By this age, puppies are starting to transition to solid food by eating the mother’s regurgitated food. However, nursing remains an important source of nutrition until puppies are fully weaned by 6-8 weeks old.
For more information see:
Cornell University College of Veterinary Medicine
PetMD
After Weaning
After the puppies are weaned off their mother’s milk, usually around 4-6 weeks old, the mother dog’s nipples will start to shrink back to normal size. However, the nipples themselves do not completely disappear.
According to experts at Rexipets, “Typically it takes 6-10 weeks for a dog’s nipples to recede after pregnancy.” [1] This allows enough time for the puppies to fully wean from nursing on their mother.
The nipples will become less swollen, prominent, and protruding as milk production ceases. But the actual nipple tissue remains on the breasts. The mother dog’s breasts will return to a flatter, less enlarged size once she is no longer producing milk for the litter.
According to Pets4Homes, “Your dam’s nipples will also begin to shrink back to size and appear less prominent the more time that passes after weaning.” [2] So while the nipples recede after weaning, they do not completely vanish.
Spaying Effects
Spaying a female dog prevents future pregnancies by removing the ovaries and uterus, but it does not cause existing nipples to disappear. The nipples that developed for nursing puppies will remain on the dog’s belly after being spayed (Do dog’s nipples shrink after spaying).
While spaying stops the production of pregnancy hormones, it does not reverse breast tissue growth that occurred during past pregnancies. According to veterinarians, the dog’s nipples may shrink somewhat over time after spaying due to reduced blood flow, but they will not completely go away (I just adopted a resue dog. She is now spayed, but her…). The existing nipple structure remains intact.
So in summary, spaying prevents female dogs from developing additional nipples with future pregnancies, but does not remove nipples already present from past litters.
Reasons Nipples May Disappear
A dog’s nipples don’t typically disappear on their own after nursing puppies. The main reasons a dog’s nipples may disappear are due to injury, disease, or surgical removal.
Injuries such as trauma, burns, or irritation can cause a dog’s nipples to become inflamed, ulcerated, or damaged to the point that they fall off. This is uncommon but can happen if the nipples are chronically irritated.
Certain diseases like mastitis (infection of the mammary glands) or cancer affecting the breast tissue or nipples may also cause nipple loss. If an infection or tumor affects the nipple structure, it can die off and fall away.
Finally, surgical procedures like mastectomy or de-sexing can remove some or all of the nipples if necessary. During spay or neuter surgery, vets may opt to remove mammary chains and nipples, especially if a dog has had recurring infections or lumps.
Aside from these reasons, it’s very rare for a dog’s nipples to disappear on their own. The nipples naturally regress in size after weaning, but don’t typically fall off without an underlying medical issue present.
Caring for Nipples
It’s important to properly care for a mother dog’s nipples while she is nursing puppies. The nipples can become irritated or infected from constant nursing. Here are some tips for caring for a dog’s nipples during this time:
Keep the nipples clean. Gently wipe the mammary glands with a warm, damp cloth before and after each nursing session. This will remove any milk residue and help prevent infection.
Watch for signs of mastitis. Mastitis is an infection of the mammary glands and can cause the nipples to become inflamed, hot, or red. The mother may act lethargic or reject the puppies. Seek veterinary care if mastitis is suspected. Antibiotics may be prescribed.
Allow the puppies to nurse frequently. Frequent nursing will help stimulate milk production and prevent the nipples from becoming overly full or engorged.
Apply warm compresses to soothe engorged or sore nipples. Make sure the compresses are not too hot as this may further irritate the skin.
Let the mother dog relax. Provide a comfortable whelping area and limit stress during nursing. Proper rest will support milk production.
Watch for signs of problem nursing. Aggressive suckling, chewing, or pulling on nipples by the puppies can cause damage. Separate problem puppies during feedings.
Wean the puppies gradually over 3-4 weeks. This allows the mother dog’s milk supply to slowly decrease as nursing demand declines.
Conclusion
To summarize, while dog nipples serve an important purpose during nursing, they do not completely disappear after weaning puppies. The mammary glands regress in size after milk production ceases, but the actual nipple itself remains present. This is because the nipple contains mammary ducts that connect to mammary tissue under the skin. Neutering a female dog can sometimes cause mammary gland tissue to shrink, which may make nipples less pronounced, but total nipple removal is unlikely. Providing proper nutrition and care during nursing can help prevent complications like mastitis that lead to damage or scarring of the nipple. With gentle cleaning and monitoring for problems, a dog’s nipples can return to a normal appearance after weaning puppies. The takeaway is that while no longer functional for milk delivery, a dog’s nipples remain a permanent part of their anatomy for life.
