Is my cat's blood really different from human blood? How so?
Hello and thank you for reaching out to Petco Pet Education Center, formerly Petcoach. Yes, cat blood is very different from human blood. There are different blood types - cats can have either A, B, or AB (rare). There is no such thing has type O in cats, as there is in humans. Humans and animals have a different PCV (packed cell volume, hematocrit) – humans: 37-50%, cat: 24-45%, that means that the number of red blood cells differs a lot between the species. There is also a huge variation between the size of the red blood cells between the species causing a different distribution of glucose in plasma. For example in humans the percentage of glucose in the red blood cells is 42%, whereas 58% of the glucose is situated in plasma. In cats (less and smaller red blood cells) there is only 7% of the glucose in the red blood cells and the majority of about 93% of the glucose is located in plasma. These are just a few of the ways that cat and human blood are different. I hope this is helpful!
Updated on September 23rd, 2025