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Mastitis in Dogs: Symptoms, Causes & Treatment

Mastitis in Dogs: Symptoms, Causes & Treatment

Mastitis often presents itself in pregnant dogs. Here, our Brentwood vets answer questions about the symptoms, causes and treatment of mastitis in female dogs. 

What is mastitis?

Some female dogs develop mastitis, a condition of swollen mammary glands. This can occur with or lead to infection. 

Typically, mastitis occurs after a female dog gives birth at home, at a site that has not been effectively sanitized. It can also result from weening newborn puppies too early. A dog can potentially develop one of a few types of mastitis, including:

  1. Acute Mastitis – The mammary gland grows painfully swollen, which can potentially lead to the mother's avoiding feeding the pups. It can also cause fatigue and inactivity. 
  2. Septic Mastitis – Inflammation of the mammary gland that leads to pain, milk discoloration, an increase in body temperature, and potential illness in the mother. 
  3. Non-Septic Mastitis – Inflammation of the mammary gland that is not caused by bacterial infection. 
  4. Gangrenous Mastitis – The teat will blacken in color. This will sometimes be accompanied by the stomach turning a darker shade. The mother may also become ill. 
  5. Chronic Mastitis – In these cases, mothers experience long-term swelling of the mammary gland. This type of mastitis is not as visible as other types, as it does not share their symptoms. 

What does mastitis look like in dogs?

Symptoms can vary greatly in dogs that develop mastitis. This is because some symptoms that affect the teat or mammary glands may or may not cause further signs of illness in the mother herself. 

If your dog is affected by mastitis, some symptoms they may experience include:

  • Discoloration of teat 
  • Swelling of the teat or mammary glands 
  • Discoloration of the milk/discharge 
  • Blood in the milk/discharge 
  • Refusal to feed puppies
  • Depressive behavior
  • Changing blood pressure or heart rate 
  • Vomiting

If your dog is displaying any symptoms listed above, please contact your vet right away

What are the causes of mastitis in dogs?

There are a few common causes of mastitis that owners of pregnant dogs should be aware of to prevent the condition from developing. Some of these causes include:

  • Bacterial or fungal infection of the teat or mammary area in pregnant dogs
  • Loss of newborn puppies resulting in the accumulation of milk
  • Milk clots or backed-up milk
  • Unsanitary whelping box
  • Damp birth site 

How dangerous is mastitis in dogs?

In most cases, mastitis in dogs is resolved without further issues, resulting in an ideal prognosis. When promptly treated, many pet owners report improvement in symptoms after two or three weeks.

When a dog experiences a severe case of mastitis, sometimes resulting in systemic, blood-borne infection, the prognosis may be guarded and it can be life-threatening. A guarded prognosis means the vet cannot accurately deliver a prognosis due to a lack of information and little insight into the potential outcome.

In some situations, it may indicate that there is nothing more that can be done, and further diagnostics or attempts at treatment may cause more harm than good.

No matter what the diagnosis is, your vet will share the information they've compiled and will be there to answer any questions that you may have.

How to Treat Mastitis in Dogs

For your dog to be treated successfully, your vet will need to diagnose the condition, including which type of mastitis your pup is experiencing. 

To diagnose mastitis, your veterinarian will perform a full physical exam, and will sometimes collect necessary information on the mother's pregnancy and labor. 

Depending on the severity and type of mastitis your dog contracts, treatment can be in the form of prescribed antibiotics or even surgery.

If the mother is still nursing her newborns, the vet will likely also gently milk the glands until the infection is completely cleared up. Milking the glands will also allow the owner or the vet to check on the level of swelling, body and skin temperature, or other conditions of the teat. Mild cold compresses may also be beneficial to help the dog feel a bit more comfortable.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Is your dog showing any signs of mastitis listed above? Contact our Brentwood vets to book an examination.

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