Dog blood banks are much like people blood banks. Donors are screened, the blood is typed, and sometimes there’s a shortage.

The U.S. is facing a dog blood shortage right now, which veterinarian Jean Dodds, who runs the Hemopet canine blood bank in Garden Grove, Calif., says is normal for this time of year.

"It happens nearly every holiday season and in summertime when epidemics of parvovirus occur," she told NPR.

The highly contagious parvovirus attacks a dog's cells, and blood transfusions are often necessary. Most of the time, dogs require donated blood for the same reasons people do: car accidents, anemia or because they're undergoing surgery.

While there’s no centralized canine blood bank for dogs, there are several independent blood banks located throughout the country, and veterinary schools often do their own blood banking.

Dodds helped start some of the first canine blood banks. She worked with animals with diseases like hemophilia, and during the early 1980s she ran New York’s human blood program, which made her realized that veterinary medicine could benefit from something similar.

Before dog blood banks existed, vets would simply call someone who owned a large dog and ask them for a donation. While this still happens today, especially in rural areas, Dodds says blood banks are better because they separate blood into plasma and red blood cells.

Packed red blood cells are used for treating trauma, as well as some cancers and autoimmune diseases. Plasma contains antibodies, which makes it useful in treating infectious diseases like parvovirus.

The shelf-life of frozen red blood cells is two months and about one year for plasma.

Doggy donors

Not all dogs are fit to donate blood, and they must undergo a screening process to determine whether they are. The first criterion is temperament — dogs aren’t sedated when blood is taken, so they must be calm and relaxed.

Canine blood donors must also be healthy, under the age of 8 and weigh more than 50 pounds.

When a dog arrives to donate blood, its paw is pricked to make sure its red blood cell count is adequate to donate. If levels are acceptable, a small area of the dog’s neck is shaved and cleaned and the dog lies on a table to have blood collected through its jugular.

Throughout the procedure, the dog is cuddled and petted and fed treats. The collection process for a pint of blood takes about 20 minutes.

"You can't communicate with a dog on a verbal level. But if we get them to the point that they're happy and they know what we want from them and they understand, then they're more likely to donate over and over again," Rebecca Pearce, a phlebotomist at the Blue Ridge Veterinary Blood Bank in Purcellville, Va., told NPR.

After processing, a pint of dog blood could help two to four canines.

Doggy donors are advised to avoid strenuous activity for 24 to 48 hours after donating. Only on rare occasions will they require fluids.

In return for their donation, dogs are often compensated with food or medicine. At the University of Florida Small Animal Hospital in Gainesville, donors receive a year's supply of preventive medicines for heartworm, ticks and fleas — to protect the blood supply — plus a 40-pound bag of food and treats.

What about cats?

Feline blood banks also exist, but, as any cat owner will tell you, cats can be a little more difficult to deal with.

Luckily, cat blood is less in demand than dog blood, according to Dr. Kirsten Cooke, a clinical assistant professor of small animal medicine at the University of Florida. The veterinary school also has an in-house cat blood bank with 10 cats enrolled in the donation program.

But blood from man’s best friend might be also be able to help cats, according to a report from New Zealand.

In August, a cat named Rory ingested rat poison and went limp, so her owner rushed her to the local veterinarian. There wasn’t enough time to test for the cat’s blood type, so the vet took a chance and used blood from a black Labrador retriever.

A wrong match would’ve proved fatal, but the interspecies transfusion was a success and today Rory is alive and well.

"Rory is back to normal and we don't have a cat that barks or fetches the paper,” Kim Edwards, the cat’s owner, told AFP.

Learn more about Rory's rescue in the video below.

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