Mammary Gland Enlargement in Cats
Written By hannah hollinger
Published: 10/08/2016Updated: 05/14/2021
Veterinary reviewed by Michele K.
Mammary Gland Enlargement in Cats - Signs, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Mammary Gland Enlargement?
While female cats are far more susceptible to these problems, nipple and mammary gland swelling is sometimes seen in male cats as well. A female who is intact is more at risk than a female that is spayed. If unusual mammary gland swelling is noticed while a cat is nursing kittens, veterinary attention may be needed for the kittens along with the mother as the infection can easily spread between the two. 
Nipple and mammary swelling are the outside manifestations of mammary gland enlargement. Most cats have eight nipples, and in the case of enlargement or inflammation, one or more nipples may be affected. Normal events in a female cat’s life can lead to the swelling of mammary tissue, such as pregnancy and lactation. However, many infections and other conditions which can be life-threatening also create mammary gland enlargement. 
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Average Cost
$600
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Symptoms of Mammary Gland Enlargement in Cats
Generally, when the condition is abnormal and needs treatment, multiple signs may arise. 
  • Swelling of the nipples or mammary tissue
  • Painful nipples
  • Redness
  • Discharge from nipples
  • Ulceration of the nipples and breast
  • Loss of appetite
  • Fever
  • Enlarged lymph nodes
  • Edema of the skin on hind legs
  • Refusal to nurse (if female with kittens)
  • Sick kittens (if nursing)
Causes of Mammary Gland Enlargement in Cats
Besides the normal cause of pregnancy, enlarged mammary glands can be the sign of a bigger internal issue in the cat. A veterinarian is best at determining the exact cause of the swelling, which will lead to a faster diagnosis and treatment for the cat. Causes include:
  • Pregnancy
  • Mastitis (mammary gland infection while lactating)
  • Galactostasis (milk collection in mammary gland while weaning)
  • Feline Mammary Hypertrophy (benign masses)
  • Mammary cancer
  • Mammary Hyperplasia (from high levels of progesterone)
Diagnosis of Mammary Gland Enlargement in Cats
A veterinarian will need the cat’s full medical history upon arrival at the clinic. A physical exam will be performed in which the nipples and mammary tissue will be closely examined for signss that match with mammary gland conditions. Some issues may not be serious and might resolve on their own, while other conditions can be life-threatening.
A range of diagnostic testing might be done, generally starting with blood work. This may include a complete blood count and a biochemical profile. A biopsy of the enlarged tissue may be taken for further microscopic evaluation (a histopathological examination). Chest and abdominal X-rays may be needed to check for tumor location and pinpoint any metastasizing (spreading). Urinalysis can be used to confirm and identify any bacteria present in the cat. 
Treatment of Mammary Gland Enlargement in Cats
There are a variety of treatments available, depending on the condition present. If the cat is dealing with an infection (as in the cases of mastitis), this can be a medical emergency. Immediate attention is needed to stabilize the cat enough to receive treatment.
Mastitis 
Treatment for mastitis includes an antibiotic prescription to clear up any infection and painkillers to help the cat endure the pain associated with this condition. Your veterinarian may also recommend that you apply a warm compress periodically to help with drainage. 
Mammary Cancer 
This type of cancer is very aggressive and often spreads. It usually occurs in multiple nipples at once. The surgical removal of affected glands (mastectomy) is recommended, especially if the cancer is in its early stages. If the cat is not a good surgical candidate, chemotherapy may be the only treatment option. 
Feline Mammary Hypertrophy 
Advised treatment for this condition is a full spay (ovariohysterectomy). While these surgeries are more routine, if the cat is suffering from poor overall health, the procedure can be very taxing. 
Mammary Hyperplasia
To alleviate this issue, removal of the source of progesterone is needed. This generally leads to an ovariohysterectomy. If ulceration of the glands has occurred, glands may be removed if the cat is stable enough. Painkillers will be prescribed to help the cat get through the days after the surgery. 
Pregnancy or Galactostasis 
Both of these causes of mammary gland enlargement will resolve on their own with time. 
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Recovery of Mammary Gland Enlargement in Cats
If the underlying condition is mammary cancer, overall prognosis is guarded. This cancer has a high tendency to spread throughout the body, most commonly to the lymph nodes, liver, kidneys, lungs and adrenal glands. If the cancer is caught early and the tumor found is less than 2cm in diameter, surgical removal offers a much higher survival rate than in more advanced cases.
If the cat has received a mastectomy or an ovariohysterectomy, signs of infection need to be watched for. Abide by all recommended at-home care from your vet. A post-surgical clinic visit is often required to allow the veterinarian to check that the healing process is happening successfully. With many of these conditions, spontaneous remissions can occur. 
Mammary Gland Enlargement Average Cost
From 433 quotes ranging from $200 - $1,400
Average Cost
$600
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Mammary Gland Enlargement Questions and Advice from Veterinary Professionals
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shorthair
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2 years
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6 found this helpful

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6 found this helpful

My pet has the following symptoms:
Lumps On Her Chest
My cat was spayed a couple of months ago. I just now noticed she has several lumps on her chest. The vet told me she was pregnant when she was spayed. I don't know if that has anything to do with them or? I'm concerned maybe the kittens have caused it. They've been weaned for a few months now but they still like to go to the momma cats and suckle them. They run about 2 - 2 1/2 inches across her stomach. She is very particular and absolutely hates having her stomach touched. They seem warm to the touch. The pictures I was able to get aren't fullly showing the swelling.
Sept. 27, 2020
Answered by Dr. Michele K. DVM
6 Recommendations
Thank you for your question. I apologize for the delay, this platform is not set up for urgent emails. If the kittens are still trying to nurse off of her, they may be causing some irritation to her mammary glands. If this problem is not improving, it would be a good idea to have her seen by your veterinarian, as they can examine her and make sure that she does not need antibiotics or other medications to help.
Oct. 10, 2020
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Cat
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Two Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
None
Hello. My cat is breastfeeding but is weaning the kittens at the moment. There is a huge mass around one the nipples. I am not sure what it is.
Sept. 26, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. It is difficult to say without being able to look at your cat, but it may be that she has an infection in that mammary gland. It would be a good idea to keep a close eye on it, and if it is not getting smaller over the next day or two, the best idea would be to have her seen by a veterinarian, as they can examine her and see what might be going. They will be able to let you know what treatment she needs once they can look at it. I hope that all goes well for her and her kittens.
Sept. 26, 2020
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Domestic Short Hair Cat
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dog-age-icon
Four Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Swollen Nipple
My cat’s nipple near her hind leg is swollen. If I gently touch it, she gets upset. She had kittens nearly 3 years ago and was spayed soon after. Other than the swelling, the nipple appears normal in color and size. Her behavior has been normal as well as her eating habits...should I be concerned?
Sept. 26, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. I apologize for the delay, this venue is not set up for urgent emails. Since I cannot see her, if you are still noticing problems with her, t would be best to have your pet seen by a veterinarian, as they can examine them, see what might be going on, and get treatment for them.
Oct. 19, 2020
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German Shepherd
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1 yr
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0 found this helpful

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My pet has the following symptoms:
Rash
rash around eye. I believe it was due to poison ivy
Sept. 20, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. Unfortunately, without seeing your dog I can't advise any medication through an email. There are many causes for rashes around the eye of young dogs, including fungal infections, bacterial infections, allergic reactions, parasites like fleas or Demodex, the list goes on. Since each of those is treated quite differently, it is difficult to say whether an ointment might help. Additionally, any ointment near the eye is a little tenuous, as you don't want any to get in the eye. If you think that the rash was caused by poison ivy, you can try washing the area very thoroughly with cool water, repeatedly, and see if that helps remove some of the irritant. If the rash is not getting better, it would probably be best to have your dog seen by a veterinarian as they can examine him and see what medication might help. I hope that all goes well for him.
Sept. 20, 2020
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Cat
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8 month
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Hard Nipples
My cat is nursing 1 week old babies, she is already on antibiotics for a slight fever and possible infection. Her bottom nipples that the kittens don’t suck on as much are hard. Is this normal?
Sept. 14, 2020
Answered by Jessica N. DVM
3 Recommendations
Hello- Thank you for your question. If the kittens aren’t nursing on certain nipples, and they are becoming hard that could indicate she is developing mastitis. I would try and place the kittens on those nipples to encourage them to eat there. If they will not and the mammary glands continue to stay hard, become red or painful you will need to take her in for a recheck with your veterinarian.
Sept. 14, 2020
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dsh
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Maggie
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15 Years
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0 found this helpful

My pet has the following symptoms:
Swollen Nipple Area
My 15 yo female DSH cat has a swelling in her back mammary gland on the left side. It is not attached to the underlying tissue but is free floating and about the size of a small grape. It is right under the nipple. I know I will need to take her to the vet but I am considered high risk for the Covid-19 virus. I have read how aggressive tumors in cats can be. Does she need to be seen now or can I wait about a month before taking her to the vet?
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Siamese
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Shiloh
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9 Months
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Enlarged Breast. Bruised Nipples
My fiancee noticed that our cat Shiloh's nipples are severely swollen...I'm not sure exactly how old she is but I'd estimate around 9 months. She experienced her first heat a few weeks ago and I caught her having sex with a male. I put a stop to it but she may be pregnant....it's all of her breasts.the appear bruised and lumpy.they are very large with purplish splotchy bruising but she doesn't appear to be in pain. I've touched them but only lightly. I rescue cats and currently have 40 ice only been able to get a few fixed so far because I support them all on a minimum wage gas station job.ive very worried please gelp
Mammary Gland Enlargement Average Cost
From 433 quotes ranging from $200 - $1,400
Average Cost
$600
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