How to treat lumps in a female cat's mammary glands:
1. If a cat develops a hard lump in its breast while it is nursing, and the kitten is already one month old, it should be weaned as soon as possible.
2. If a non-lactating cat develops a lump in its breast, you can try applying a warm compress and observe if the lump disappears. However, if the lump does not disappear after applying a warm compress, you need to take it to a veterinary hospital to rule out whether it is caused by a breast tumor, in which case surgery may be necessary. 
How to relieve engorgement in a mother cat:
1. Gently massaging the mother cat's breasts can help reduce the lumps.
2. Apply a hot compress twice a day, each time for about 10-20 minutes, which can help reduce the hardening.
3. You can use a pet breast pump to express excess milk from the mother cat's breasts and unclog the milk ducts. If the breast lump is caused by mastitis, the owner will need to give the mother cat some anti-inflammatory medication.
4. If the cat's engorgement lasts for more than a week or does not subside over a long period of time, then you need to take the cat to the vet for treatment in time.
