A revolution in zoo care? Brookfield veterinarian working to build red blood cell bank for zoo, aquarium animals

Brunei the orangutan is a good sport when Dr. Lily Parkinson draws some blood.

“I'm finding his blood vessel on the ultrasound, and then poking it and getting blood, which was very cooperative of him,” she says, showing a video of a great ape more interested in a Jell-O treat than the collection process.

It’s only a glimpse into her work at Brookfield Zoo Chicago. Parkinson, a clinical veterinarian, is researching the viability of a long-term frozen red blood cell bank for zoo and aquarium animals.

“The idea of having a bank available with a lot of research already completed about how best to cross-match different species is a huge peace of mind that we might be able to have for the future,” said Dr. Karisa Tang, vice president of animal health at the Shedd Aquarium in Chicago. “So it could just really give us a resource that doesn't exist for zoological species.”

The problem with freezing cells? When you put them in a freezer normally, ice crystals form, and then they burst the cell membrane and “make your cells no longer cells,” Parkinson said.

“Tons of humans need transfusions every day, but it is very rare to never happens, hopefully, that some of our species need a transfusion,” Tang said. “So it’s not like keeping it reliably in the refrigerator often is practical.”

And arranging a blood donation for, say, a zoo carnivore or a member of a critically endangered species is certainly not as simple as rolling up your sleeves, to put it in human terms.

“We have sent some of our blood products to a sick rhino before. I know we've gotten contacted about gorillas that are ill around the country, and we have blood here,” Parkinson said. “It's definitely a whole reaching out to each other and talking to each other and seeing who has what and what can be done.”

Polar bears are among the Brookfield Zoo Chicago residents trained for voluntary blood draw sessions. In other cases, the donor animal is anesthetized.

“You’re collecting it and trying to give it right away, or trying to keep it on an ice pack where it’s not getting frozen, but it’s being refrigerated while it’s shipped where it’s going and then given right away,” Parkinson said.

She’s trying to change that.

An ‘amazing project’

While doing research on red blood cells, Parkinson discovered that they could withstand freezing when mixed with a special solution, she said in a zoo video about her latest project.

“It was working really well, so then I thought, well, maybe we could start a transfusion red blood cell bank,” Parkinson said on a recent morning in the zoo’s animal hospital.

The Shedd has contributed to the project, thanks to its preparations for the July 2024 birth of a beluga calf, since named Opus. Beluga babies need special milk, which “has a lot of really great immune components to it,” Tang said. And if they don’t nurse right away, it can be helpful to administer plasma, the liquid portion of blood, to boost antibodies. “So we collected blood from our whales at Shedd Aquarium,” Tang said.

Brookfield happens to have a centrifuge that spins blood to separate plasma from cells.

“So it was a perfect segue into ‘well, if you don't need these red blood cells right now, would you be interested in collaborating on this blood bank project?’ And so, of course, we're very excited for anything that we can do to help this amazing project,” Tang said.

Omaha's Henry Doorly Zoo & Aquarium has also provided elephant blood. At Brookfield, blood has been collected from various creatures during routine exams. Parkinson, a kind of MacGyver, uses a sterile tubing welder to make “tiny, little individual blood collection sets for our tiny animals.”

“Dr. Lily is one of the smartest people you will ever come into contact with. She is double boarded in zoological medicine and emergency and critical care, which is absolutely wild already,” Tang said.

Parkinson uses yet another machine, an automated cell processor, to add that glycerol solution to the red blood cells. The samples are staying in an extremely cold research freezer for six months.

Parkinson will soon begin thawing the samples and removing the glycerol solution. Then, she will take a look at the cells under the microscope.

“Do they all look like they're supposed to, with the right shape and size and all that? And then we have some tests that we're able to run here to see how their metabolism is working,” she said.

A lifeline

Parkinson is most optimistic about giraffe and elephant samples, though she’s careful to manage expectations.

“I definitely, unfortunately, don't think that anything is going to work universally across the board,” Parkinson said. “But there are a lot of really smart people on the human side that are working on creating better freezing solutions.”

She would not be unhappy if it’s only successful for giraffes and elephants. Elephant endotheliotropic herpesvirus, or EEHV, attacks the blood vessel linings of young calves. Other institutions are “keeping just the plasma for that emergency situation where they don't want to take the time to run over to the adult and collect the blood,” Parkinson said.

She’s motivated by the desire to provide the best medicine for the animals in her care. And to help her colleagues.

“So that they don't have to worry about anything else,” Parkinson said, “except for their really sick patient that's in front of them, which is plenty to worry about.”