KANSAS CITY, Mo. (AP) — Treating elephant arthritis is among the challenges the Kansas City Zoo is facing as its animals live longer.

Zoos have for years steered away from rejuvenating their collections with wild-born species unless deemed vitally necessary because of captive breeding and wild animal conservation becoming a priority.

The zoo’s chief veterinarian, Kirk Suedmeyer, estimated that some 25 percent of the zoo’s 1,100 animals are what would be considered geriatric.

Since late July, a 47-year-old African elephant named Lady has been receiving inflammation-reducing laser therapy to help soothe arthritis.

The zoo also has trained its aged silverback gorilla, Radi, to present his chest for regular echocardiograms using a portable wand.