It’s cat-dog! Florida Keys feline gets blood transfusion from canine

A Key West cat has some bark in its blood following a blood transfusion -- from a dog -- last month.

On Sept. 16, Dr. Sean Perry from the Marathon Veterinary Hospital conducted the lifesaving transfusion on Buttercup, an orange tabby, using dog's blood. The transfusion, known as a xenotransfusion, is a rare procedure in which cats can continue to generate red blood cells after they're fused with dog's blood.

The transfusion — the blood came from a West Palm Beach dog blood bank (they exist) — lasted four hours and was suggested after veterinarians told Buttercups owner, Ernie Saunders, that it would take days and possibly weeks to have cat blood shipped to the Middle Keys. Dog blood, which the hospital already had, was an immediate alternative.

"It's a situation where you can't give type A blood to a type B blood cat because it'll cause a severe immune reaction," Perry said. "It was actually safer to give the cat dog's blood. It's a practice that's been used in the past but it's not common."

Saunders became concerned after Buttercup became too lethargic, even by cat standards.

After a few tests, veterinarians learned Buttercup's red blood cell count was down to 7 percent, making him anemic. Perry said cats should have a red blood cell count of at least 35 percent. That led to the need for a transfusion.

"Cat's blood is a little harder to come by and not as available as dog's blood," Perry said. "We had greyhound blood packs that we get from a blood bank that has red blood cells separated from plasma. Buttercup showed no signs of rejection during the transfusion."

Perry said as far as veterinarians know, cats are the only animal that accept transfused blood from dogs.

According to the U.S. National Library of Medicine, 62 cats have been known to have a xenotransfusion.

Cats lack antibodies against canine red blood cell antigens, a substance that causes the immune system to react. After the transfusion, however, the cat's immune system will build the antibody — a protein in an animal's immune system that reacts to potential threats — against the canine antigen, limiting the xenotransfusion to a one-time procedure.

Perry said should Buttercup receive any more dog's blood, the cat's immune system would go into attack mode.

Saunders said Buttercup has been more active since the procedure and continues to take steroids and antibiotics. Buttercup now has regular checkups at the Marathon Veterinary Hospital.

Saunders also learned his cat had a bit of an identity crisis. “I found out he was a male instead of a female," Saunders said. "I let a charter guy's daughter name it Buttercup. Personally, I just call him Kitty."

Veterinarians are unsure why the cat's red blood cell count got so low.