07/07/2026
Did You Know Dogs and Cats Have Different Blood Types?
Most people are familiar with the human ABO and Rh blood typing system, which includes four blood types (A, B, AB, and O) that can each be either Rh-positive or Rh-negative, resulting in eight common blood types.
But did you know our pets have their own unique blood typing systems?
Canine Blood Types
Dogs are typed using the Dog Erythrocyte Antigen (DEA) system. The most clinically important blood type for transfusions is DEA 1.
β’ DEA 1 Negative β These dogs do not have the DEA 1 antigen and are considered universal donors. They can donate blood to both DEA 1-negative and DEA 1-positive dogs but can only receive DEA 1-negative blood.
β’ DEA 1 Positive β These dogs have the DEA 1 antigen and can receive either DEA 1-negative or DEA 1-positive blood in many clinical situations, making them more flexible recipients.
Feline Blood Types
Cats use the AB blood group system, but it is different from the human ABO system.
β’ Type A β The most common blood type among domestic shorthair cats in the United States. These cats have antibodies against Type B blood and should not receive Type B blood.
β’ Type B β Less common overall but seen more frequently in certain purebred cats and in regions such as Italy, France, and Australia. These cats have strong antibodies against Type A blood and must not receive Type A blood.
β’ Type AB β The rarest feline blood type. These cats do not have naturally occurring antibodies against either Type A or Type B blood and can generally receive blood from either type, although compatibility testing is still essential.
Blood Products We Keep on Hand
At SOVSC, we strive to maintain a supply of DEA 1-negative canine packed red blood cells (PRBCs) and Type A feline PRBCs so we're prepared for emergencies involving our furry patients.
Packed red blood cells (PRBCs) contain the red blood cell portion of blood with most of the plasma removed. This allows us to deliver a concentrated source of oxygen-carrying red blood cells to patients suffering from anemia.
We are also fortunate to have employee-owned canine and feline blood donors available if whole blood is needed. Whole blood contains red blood cells, plasma, platelets, and clotting factors, making it especially valuable for patients with significant blood loss or clotting disorders.
Why Crossmatching Matters
Before a blood transfusion, we perform a crossmatch to help ensure the donor's blood is compatible with the recipient's.
During this test, the recipient's blood components are mixed with the donor's red blood cells to determine whether the recipient's immune system will react against the donor blood. If a reaction occurs, a different donor is tested until a compatible match is found.
Crossmatching is an important step that helps minimize the risk of transfusion reactions and provides the safest possible care for our patients.