Lomelok, born in January 2023, underwent spinal surgery to address a herniated disc in March 2024. A surgery first of its kind, according to the Zoo.
The cub's recovery was slow and steady, however, the zoo said it was clear the lion was not going to have a full recovery.
The zoo said Lomelok recently developed a gastrointestinal obstruction that would require another intense surgery.
Due to the long recovery that second surgery would require, the zoo decided to pursue euthanasia.
His pride of brothers Pesho, Sidai, and Pilipili will be monitored.
"Lomelok's story spread far & wide. This loss will be felt by so many. Our teams are hurting and we are grieving. Our hearts go out to everyone who cared about this special lion," the zoo said on X.
In March, the Lincoln Park Zoo announced the death of beloved Bana, a western lowland gorilla.
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