Officials at Zoo Miami are mourning the loss of a 12-year-old Malayan tiger named Tevy.

The female tiger was found dead in her enclosure Monday morning, according to Zoo Miami spokesman Ron Magill.

Magill said zookeepers had noticed Tevy acting lethargic about a month ago. She recovered but began suffering from the same symptoms last week.

During an exam Sunday, veterinarians discovered that the tiger was severely jaundiced, and a course of treatment was planned. She died before completing treatment.

A necropsy performed Monday showed Tevy died from advanced liver failure. More tests are being performed to determine the definitive cause of death.

Tevy was born February 28, 2000 at the Cincinnati Zoo and arrived at Zoo Miami from the Knoxville Zoo in 2010 as part of a carefully planned breeding program. Malayan tigers are highly endangered.