Can A Dog Get Mastitis Without Having Puppies?

What is Mastitis?

Mastitis is inflammation of the mammary glands, which is often caused by a bacterial infection. It typically occurs in females who are breastfeeding, but can also occur in women who are not lactating, males, and other animals with mammary glands such as dogs and cats. The inflammation results in swelling, redness, and pain in the breast tissue. If left untreated, mastitis can lead to the formation of abscesses in the breast. It is considered a medical emergency that requires prompt treatment with antibiotics and other therapies.

Mastitis is most commonly caused by the bacteria Staphylococcus aureus. It can spread through cracks or fissures in the skin of the nipple, or when milk builds up in the breast, allowing bacteria to multiply. Risk factors include breast engorgement, nipple damage, blocked milk ducts, and a weakened immune system. Mastitis often comes on suddenly with symptoms like a breast lump, swelling, warmth, and redness on the affected breast. Other symptoms may include fever, chills, and fatigue.

While mastitis most frequently occurs in breastfeeding women, it can also develop in women who are not nursing, as well as males and animals with mammary glands like dogs. The mammary glands become inflamed due to bacterial infection. When mastitis occurs outside of lactation, it is sometimes referred to as non-puerperal mastitis. Prompt medical treatment is required for any case of mastitis to prevent complications.[1]

Mastitis in Dogs

Mastitis is inflammation of the mammary glands and most commonly occurs in lactating female dogs. However, it can also occur in dogs that have not recently whelped or lactated. The mammary glands can become infected and inflamed for various reasons.

In lactating dogs, mastitis usually develops within 3 weeks after whelping. It is often caused by bacterial infection that enters through cracks or wounds in the skin of the teats. Dogs with mastitis may appear normal other than the affected mammary gland, which appears swollen, painful, and may leak pus. Other symptoms can include fever, lethargy, loss of appetite, and neglecting the puppies.

In non-lactating dogs, the cause is often unknown but may be due to hormonal influences, trauma, or cysts. The mammary glands may feel firm or fluid-filled. Skin discoloration, pain, and abnormal secretions can occur. Dogs may lick or bite at the area due to discomfort.

Mastitis is diagnosed through physical examination, palpation of the mammary glands, bacterial culture of the milk or tissue, and sometimes imaging tests like ultrasound. Treatment involves antibiotics, anti-inflammatories, and warm compresses. Sometimes the affected mammary tissue may need to be surgically removed. Prognosis is generally good with prompt treatment.


Causes of Mastitis in Non-Lactating Dogs

Mastitis can occur in female dogs who are not actively nursing puppies. There are several potential causes for mastitis in non-lactating dogs:

Hormonal imbalances may lead to mastitis, as hormones regulate mammary gland function. Conditions like false pregnancy or irregular heat cycles can cause hormone fluctuations that disrupt normal mammary activity and increase infection risk.

Obesity is another risk factor, as excess fat can limit blood flow and cause inflammation in mammary tissues. Obese dogs tend to have weaker immune systems as well, making them more prone to infection.

Mammary tumors are a serious cause of mastitis in non-lactating dogs. Tumors obstruct ducts and damage glandular structures, allowing bacteria an entry point. Mastitis may be the first clinical sign of an underlying mammary tumor.

Physical trauma to the mammary glands, like cuts, punctures or bruising, can introduce bacteria and lead to infection and mastitis. Trauma may occur from playing, bites, falls or other accidents.

Treatment Options

Treatment of mastitis will depend on the cause and severity. Mild cases may be treated with antibiotics and anti-inflammatories alone. More severe cases often require additional treatment such as draining abscesses or even surgical removal of the affected mammary glands.

Antibiotics are commonly used to treat mastitis. Broad-spectrum antibiotics like amoxicillin or cephalexin are typically used initially to cover a wide range of potential bacteria. Your veterinarian may culture the infected tissue to identify the specific bacteria involved and target treatment accordingly. Antibiotics are usually given for 2-4 weeks.

Anti-inflammatory medication like carprofen or meloxicam help reduce swelling, pain, and fever. This provides additional comfort for the dog as the infection is treated.

Abscesses may form within the infected mammary tissue. Draining these abscesses helps remove the infected material and allows the antibiotics to work more effectively. This may be done by needle aspiration or surgical incision depending on the size and location.

In severe recurrent cases, surgical removal of the affected mammary glands (mastectomy) may be required. This eliminates the infected tissue and prevents the infection from returning.

Some home remedies like hot compresses may provide comfort but are not a substitute for veterinary treatment. Most cases of mastitis require medication prescribed by a veterinarian for an effective cure.



There are a few key ways to help prevent mastitis in dogs:

Spaying your dog is one of the most effective ways to prevent mastitis, as the surgery removes the mammary glands and hormones that can lead to mastitis. Dogs spayed before their first heat cycle have just a 0.5% chance of developing mammary tumors.

Maintaining your dog’s ideal weight can also lower the risk of mastitis. Obesity leads to more inflammation and can make detection of lumps harder. Feed your dog a healthy diet and ensure regular exercise.

Regularly check your dog’s mammary glands for any lumps, swelling, discharge or redness. Early detection of any changes makes treatment easier. Contact your vet immediately if you notice anything abnormal. Checking after heat cycles or pregnancy is especially important.

Good hygiene and cleaning of the mammary glands, especially when nursing puppies, helps prevent infection. Gently wipe with a warm, wet cloth after feeding.

Consider preventative mastectomy if your breed is prone to mammary cancer. This surgical removal of mammary glands can greatly reduce the chances of mastitis. Discuss options with your veterinarian.


If a dog is diagnosed with either acute or chronic mastitis, the prognosis is usually good with prompt treatment, according to PetMD[1]. The infection and inflammation typically clear up within 2-3 weeks when antibiotics and anti-inflammatory medications are administered right away. However, there can be potential complications if mastitis goes untreated for too long. These include the spread of infection to the bloodstream or other parts of the body, gangrene or tissue death in the mammary glands, chronic recurring infections, and the formation of abscesses or cysts in the breast tissue. Dogs that have had mastitis once are also at a higher risk of developing mastitis again in the future, especially during subsequent pregnancies or false pregnancies. Close monitoring and preventative care is important for dogs recovering from mastitis to avoid recurrence and detect any persisting issues with the mammary glands.

When to See a Vet

It’s important to contact your veterinarian if your dog develops signs of mastitis. Some signs that indicate it’s time to see the vet include:

Persistent swelling or redness in the mammary glands: Swelling, redness, and heat are common symptoms of inflammation and infection. If these symptoms persist or get worse, it signals the mastitis is not improving on its own. (VCA Hospitals)

Signs of infection like pus or a foul odor: Purulent discharge or a foul/rotten odor from the nipples likely indicates infection. Infectious mastitis requires prescription antibiotics to clear. (WebMD)

Nipple discharge: Any nipple discharge outside of the lactation period warrants a vet visit. Discharge may be pus from infection, milk from hormonal issues, or blood from injury/cancer. Identifying the cause helps guide treatment. (WagWalking)

Lumps or swelling in the mammary glands: Non-painful lumps could indicate mammary tumors rather than mastitis. Rapidly growing lumps should always be checked as soon as possible. (VCA Hospitals)

Caring for a Dog with Mastitis

Caring for a dog with mastitis requires diligent at-home care and following your veterinarian’s instructions closely. Some key aspects of caring for a dog with mastitis include:

Providing Medication – It’s crucial to give all prescribed antibiotics and pain medications as directed by your vet. Completing the full course of antibiotics, even if your dog seems better, helps ensure the infection is fully eliminated (VCA Hospitals).

Keeping Incision Sites Clean – For mastitis cases treated surgically, keep the incision site very clean by using an Elizabethan collar and cleaning the area with antiseptic solution recommended by your vet. Watch for signs of infection like discharge or swelling (AKC).

Restricting Activity – Limit your dog’s activity to allow them to rest and heal. Take short, gentle leash walks for bathroom breaks only. Avoid running, jumping, rough play, and other strenuous activity that could aggravate the condition (WebMD).

Your vet may also recommend warm compresses, gentle massage of the mammary glands, a nutritional supplement, or other supportive care. Follow your vet’s advice closely to help your dog recover as comfortably and quickly as possible.

Cost of Treating Mastitis

Treating mastitis in dogs can be quite expensive depending on the severity of the condition. Some of the costs involved include:

Exam and Diagnostics Fees: The initial veterinary exam to diagnose mastitis may cost $50-$250. Additional diagnostics like bloodwork, cultures, and x-rays can cost $150-$500 to help identify the underlying cause and best treatment plan (Source).

Medications: Antibiotics, anti-inflammatories, and pain medications may be prescribed to treat mastitis, ranging from $30-$150. Severe or chronic cases may require extended medication therapy (Source).

Surgery: In some cases where medications fail, surgery may be required to remove infected mammary glands or drain abscesses. Surgery can cost $300-$800 depending on the extent of tissue removal needed (Source).

Additional nursing care, follow-up vet visits, and potential complications can also add to the cost of treating mastitis. Pet insurance can help offset expenses, with mastitis treatment averaging $500 (Source). Discuss budget and options with your vet to provide the best care for your dog.

Mastitis in Other Animals

Mastitis can occur in various animals that lactate, such as cows, cats, sheep, goats, and llamas. It is most commonly associated with lactation and breastfeeding, as infections can develop and spread through the mammary glands. However, mastitis can also occur outside of lactation in intact females of these species.

In dairy cattle, mastitis is the most common and costly disease, usually occurring during lactation. According to research, various factors can increase the risk of mastitis in cows, including poor hygiene, teat damage, nutritional deficiencies, and stress. While antibiotics are commonly used for treatment, prevention involves proper milking procedures, teat disinfectants, and maintaining clean housing environments.

Feline mastitis is less common but can still occur outside of queening. Usually it is caused by trauma, blocked milk ducts, or bacterial spread. Treatment involves pain control, antibiotics, and sometimes surgical drainage. Prognosis is generally good with prompt care. Mastitis has also been reported in ewes, does, and llamas not currently lactating or raising young. However it appears more prevalent during lactation periods.

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