TL;DR: Mastitis is a painful and potentially life-threatening mammary gland infection in dogs that requires urgent veterinary attention. Seek emergency care immediately if your dog shows signs of fever, lethargy, or if the mammary glands are severely swollen, hot, or discolored.
What is dog mastitis and how does it affect my pet?
Mastitis is an inflammation or bacterial infection of the mammary glands. This condition is most common in nursing dogs but can occasionally occur during a false pregnancy or in any female dog. The infection causes the milk ducts to become blocked and inflamed, leading to glands that feel firm, swollen, and abnormally hot to the touch. In severe cases, the milk may appear discolored, bloody, or thick.
Is dog mastitis considered a veterinary emergency?
- Mastitis is a high-urgency condition that is extremely painful and can escalate rapidly into life-threatening sepsis.
- Seek emergency veterinary care immediately if your dog is lethargic, refusing to eat, or has a fever.
- Immediate attention is required if mammary glands turn dark purple or black, which indicates tissue death.
- Prompt treatment with antibiotics and pain management is essential to prevent the infection from spreading to the bloodstream.
Why should I provide a photo of my dog's symptoms for veterinary triage?
- Visual evidence allows a triage nurse or veterinarian to assess the degree of inflammation and look for abscesses.
- Photos help identify skin discoloration that may indicate dangerous gangrenous mastitis.
- Seeing the area helps the clinical team determine how quickly your dog needs to be seen.
- Providing an image prepares the team for the specific type of care required upon your arrival.
Clinical Context (Merck Veterinary Manual)
In acute mastitis, affected mammary glands are typically hot and painful. Systemic signs such as fever, depression, anorexia, and lethargy may indicate progression to septic mastitis, requiring prompt veterinary attention. Milk from each gland should be evaluated in any postpartum bitch with signs of systemic illness, and a milk sample should be collected via fine-needle aspiration for bacterial culture and sensitivity testing before initiating therapy. Broad-spectrum, bactericidal antibiotics, such as cephalexin (5-15 mg/kg, PO, tid) or amoxicillin/clavulanate (14 mg/kg, PO, bid-tid), are recommended as initial therapeutic agents pending culture results, considering their passage to the neonates. Hot-packing the affected gland encourages drainage and can relieve discomfort. Fluid therapy is indicated in animals with septic mastitis that are dehydrated or in shock.
Chapter: Infectious Diseases, Reproduction
Source: The Merck Veterinary Manual, 11th Edition (Page 1396)