The Oklahoma City Zoo continues to be a leader in the field of animal medicine, innovating a new stem cell-based treatment to improve blood flow and shorten recovery time. When geriatric elephant Bamboo, 53, experienced a minor tail wound, veterinary staff came together and made a plan to help accelerate healing. Tails have smaller blood vessels and take longer to heal, especially in older animals. The OKC Zoo veterinary team decided to launch a two-pronged treatment approach. First, the traditional wound care and antibiotic regimen. Second, a novel treatment never before attempted in elephants for wound care: stem cell therapy.

“Stem cell therapy is routine in human medicine and becoming more accessible for animal patients – it’s already common in dogs and horses,” said Jennifer D’Agostino, OKC Zoo director of veterinary services. “We are discovering some of the benefits of stem cell treatment for our wildlife species include reducing inflammation and increasing blood flow. Other zoos have had success using the therapy in elephants for arthritis but the OKC Zoo is the first to use the therapy for elephant wound care. We are just beginning to explore the vast potential stem cell therapy offers for wildlife medicine.”
Stem Cells 101
Stem cells possess the ability to become other, more specialized types of cells, and they become whatever other type of cell they are near. It’s this capability that makes stem cells valuable for medical purposes. In the early days of stem cell research, the only known way to extract the cells was from embryos. This is no longer the case. Unlike embryonic stem cells, mesenchymal stem cells can be cultivated from a variety of different sources including bone marrow, adipose (fat) tissue and whole blood. The stem cells used to treat Bamboo were obtained from whole blood. These can be harvested from an individual’s own blood, but since Bamboo is geriatric and no longer produces adequate stem cells herself, donor cells were provided from younger elephants.
The Treatment
When researching treatment options, the Zoo consulted Dr. Valerie Johnson at the Colorado State University Center for Immune and Regenerative DVM Medicine. Dr. Johnson’s team had previously used stem cell therapy to treat elephants for other conditions and grows mesenchymal stem cells from donated elephant blood. It takes about four weeks to grow stem cells and another two weeks to “expand” them, letting the cells multiply. Dr. Johnson was on-hand during the first round of Bamboo’s stem cell treatment and will continue to provide assistance.

In a process very similar to a blood collection, the treatment was administered via intravenous stem cell injection into an ear vein and an injection at the wound site. Blood collections are a medical behavior that all the Zoo’s elephants are trained for and voluntarily participate in on a weekly basis. Bamboo voluntarily participated in her treatments in exchange for some of her favorite treats (watermelon, cantaloupe, bananas). The elephant care team treats the wound on a daily basis, scrubbing the tail with a chlorohexidine solution and applying a topical antibiotic (SSD cream). The veterinary team reports the wound looks good and is healing slowly.
About Bamboo
At 53, Bamboo is the oldest of the Zoo’s Asian elephant 7-member herd. The median life expectancy of the species is 46.9 years. Caretakers describe her as grandmotherly and introverted, enjoying social time with the other elephants in the herd but also doing things alone. Bamboo has formed a close bond with male, Kandula, 17. The two have spent almost every day together since spring 2016. Sometimes elephants will put another elephant’s tail in their mouth and if the other elephant pulls away, this can cause the skin to be scraped or tail hair to be pulled. It’s likely that Kandula playfully bit Bamboo’s tail and caused the wound.

How the OKC Zoo Helps Elephants
The OKC Zoo participates in the Asian Elephant Species Survival Plan (SSP), developed by the Association of Zoos and Aquariums (AZA). Asian elephants are endangered and their African counterparts are vulnerable. Currently, the greatest threats to Asian elephants are habitat destruction and human-elephant conflict. About 60 percent of the total human population lives in Asia, and this population has nearly quadrupled in the last century. As human needs increase, more natural land is taken away from Asian elephants in order to build cities, homes, highways, farmland, etc. Habitat destruction is forcing animals, elephants in particular, to come in contact with humans in ways that can cause conflict.
In addition to supporting the Northern Rangelands Trust since 2009, which protects African elephants, the Zoo has been working with Rainforest Trust to purchase and preserve 13,000 acres of forest in central Sumatra and 18,000 acres of forest in Borneo, both of which are natural habitats for Asian elephants. The OKC Zoo also helps support a number of other elephant conservation projects, including the Wildlife Conservation Society’s Rakhine Yoma Elephant Range Project in Myanmar and International Elephant Foundation’s conservation efforts in Sumatra. These projects support boots on the ground teams that protect forests, prevent poaching and encroachment and mitigate human-elephant conflict. Since 2010, the Zoo has contributed almost $400,000 to elephant-related conservation.
Photos courtesy Andrea Johnson