Cats have three main blood types — A, B, and AB — plus at least one additional blood group (Mik) identified more recently. So the simple answer is:
Cats have 3 major blood types, and at least 1–5 additional minor blood groups.
🩸 Core feline blood types
- Type A — the most common worldwide (including Japan).
- Type B — less common; more frequent in certain pure breeds.
- Type AB — very rare.
These three make up the feline AB blood group system, which is not the same as the human ABO system.
🩸 Additional blood groups
In 2007, researchers discovered a new blood antigen called Mik, and since then 4–5 more feline erythrocyte antigens (FEA 1–5) have been identified.
These FEAs matter for transfusions because even if the A/B/AB type matches, a cat can still react badly if the Mik/FEA types are incompatible.
Why this matters
- Cats naturally have strong antibodies against foreign blood types.
- A mismatched transfusion can cause rapid, life‑threatening hemolysis.
- There is no universal donor cat.