Wild animals that are bred in captivity are often a core part of projects that aim to restore wild populations of that might otherwise go extinct. Thus, it is important to ensure the best quality of life of captive animals, both for welfare reasons, as well to maximise their contributions for such conservation and re-wilding projects.

Recent Cases from zoos around the world:

There are several noteworthy cases of improving arthritis in zoo animals by stem cell treatments in recent years.

For example, in 2018 a 32-year-old polar bear in the Point Defiance Zoo received stem cells that were harvested from its own fat tissue showing moderate alleviation of the symptoms. Further successful results from autologous (stem cells coming from the patient) treatments were observed in a number of mammalian species: a very good improvement of old age associated arthritis was achieved for an Asian pig in the Houston Zoo.

More recently, a 17-year-old colobus monkey received a stem cell treatment for spinal arthritis in the Mesker Park Zoo and Botanical Garden in 2020, which helped the animal to start moving after several months of very limited mobility. 

The veterinary programme of Colorado State University grew stem cells from a giraffe’s blood in order to treat its chronic arthritis. The veterinarians in the Cheyenne Mountain Zoo observed significant alleviation of the symptoms after combining stem cell therapy with other treatments just after a few weeks. Similar to giraffes, tigers are also prone to develop arthritis due to their large size and require that close attention is paid to the state of their joints. However, stem cell treatment can be used even in cases of advanced stage of the disease. For example, a successful autologous treatment on a Siberian tiger in Szeged Vadaspark, Hungary who developed hip arthritis. In a similar case in Sydney, Taronga Zoo, mesenchymal stem cells from fat tissue were used to slow down knee osteoarthritis in a snow leopard which was the first-time stem cell treatment was performed on a big feline in Australia . 

Stem cells also proved to be very effective in assisting wound healing and restoring tissues after injury, so experimental stem cell treatment for such cases was also attempted in a number of Zoos. A Bengal tiger in the Mexican Zoo was hit by rubble during a hurricane which left him only being able to scoot on the ground. The animal might have been euthanized without the mesenchymal stem cell treatment that was offered by InGeneron. Following treatment with autologous stem cells that were injected into the tiger’s hips and knees, it fully restored his ability to walk .

Another example of assisted wound healing but this time with allogenic stem cells (coming from a donor, different from the patient) was observed in Oklahoma City Zoo. Veterinarians used stem cells from elephant blood donated to the Colorado State University Center for Immune and Regenerative DVM Medicine to treat a tail wound in a 53-year-old elephant. A tail has a limited blood supply and wound healing is generally much slower in old animals, but combining stem cell injection at the wound site with topical antibiotics and other treatments, accelerated successful wound healing.

All these successful cases provide a growing evidence-base that the use of stem cells in mucoskeletal and injury settings may be a beneficial approach in a number of mammalian species, beyond their experimental treatments that often focus on domestic and companion animals.