Managing Mastitis in Nursing Queens: A Guide for Cat Breeders

Please note, I’m a Human doctor not a vet but I have taken this information from the latest specialist advice in Human medicine. I’ve also had a (Human) Lactation Medicine specialist in training (Dr Beth Harrison), Human Breast surgeon (Dr Nicola Davis) and Lactation consultant (Vicki Paterson -who is also a cat breeder) all input into this article.

Mastitis, an inflammation of the mammary ducts, can be a concerning issue for cat breeders. Early recognition and prompt management are crucial to ensuring the health of both the queen and her kittens.

Recognizing Mastitis -Mastitis typically starts with inflammation of the ducts of the mammary glands which can happen as the milk “comes in” or via trauma or some other cause. These areas of periductal inflammation give the sensation of ‘blockage’, but it’s not actually pockets that need draining, it’s inflammation, compressing ducts. These areas provide an ideal environment for bacteria to grow if the milk is allowed to sit around, leading to infection if not drained appropriately. So the aim is to remove inflammation with physiological feeding.  

The best way to drain these pockets? Your tiny little sucking machines — the kittens! Keeping the kittens feeding regularly is the most natural and effective treatment.

Treatment and Management The cornerstone of managing mastitis is keeping the kittens nursing. Frequent feeding helps to empty the glands, prevent stasis, and promote drainage, which is essential for recovery. To protect the queen’s delicate skin, clip the kittens’ claws gently to prevent scratching and further injury. Dr Beth Shore recommends ice packs although recognises this may be difficult in cats! Dr Nicola Ross also recommends feeding on demand, ie not forcing feeding or massaging the breast to get the milk flowing as this can result in more trauma & inflammation.

Antibiotic therapy is only needed if the queen becomes unwell, showing signs such as fever and malaise. In these cases, antibiotics like clindamycin or flucloxacillin are appropriate, targeting common skin pathogens. In humans, if an abcess forms, needle aspiration is preferable (as long as the skin isn’t threatened) to prevent a milk duct fistula. Aspiration usually needs to be done a few times before things settle.

It is perfectly safe for kittens to continue nursing even if there is infection. The antibiotics and anti-inflammatory medications prescribed are secreted into the milk in only minimal amounts and will not cause any harm to the kittens. The kitten’s stomach acid will kill any bacteria in the milk.

Supportive care with non-steroidal anti-inflammatory drugs (NSAIDs) eg Metacam, can help reduce pain and inflammation. Again, NSAIDs are safe to use while kittens are feeding when prescribed appropriately.

Differential Diagnosis: Galactocele Not all lumps in the mammary glands are mastitis. Another possibility is a galactocele—a milk-filled cyst that forms when a duct becomes blocked without infection. Galactoceles are usually non-painful, but continued nursing is still the best way to encourage drainage and resolution.

Key Points for Breeders

• Keep kittens nursing — the best and most natural treatment.

• Clip kittens’ claws to minimize trauma to mammary tissue.

• Reserve antibiotic therapy for queens who are unwell with fever or malaise.

• Use flucloxacillin or clindamycin if antibiotics are needed, both safe for nursing.

• Administer NSAIDs for pain relief under veterinary advice.

• Safe to keep kittens feeding — even if the queen is infected and on medication.

• Monitor closely and seek veterinary support if there’s no improvement.

With early attention, a little supportive care, and those busy little "milk pumps" working hard, most queens recover fully and continue raising their litters successfully.

(picture below, Glitterpaws Queen Elizabeth and her cute little sucking machines!).