Zoo Knoxville's only gazelle died overnight Thursday just days after he escaped his enclosure in the Grasslands Africa habitat.

Fodder, an 11-year-old Thomson's gazelle, escaped the enclosure around 10:30 p.m. Sunday. He was spotted and tranquilized around 8:30 a.m. Monday.

Fodder underwent surgery at the zoo's medical center for a broken jaw. Veterinarians placed a wire in his jaw to repair the break.

Zoo officials said Fodder was standing and more alert on Tuesday, but had not attempted to eat at that point.

"It was determined yesterday that the wire placed in his jaw was not holding the bone and another surgery was done to allow him to eat," Zoo Knoxville wrote in a Facebook post Friday.

Fodder initially appeared to handle the surgery well, but did not recover and died overnight Thursday, the zoo said.

"(Fodder) received the best care and consideration for his quality of life possible, thanks to his keepers and vet team, and his advanced age was a testament to their commitment," the zoo said.

Tina Rolen, director of communications for Zoo Knoxville, said a necropsy will be done at UT College of Veterinary Medicine to determine the cause of death.

Zoo staff said earlier this week that they believed Fodder may have jumped over the fence because he was spooked by something. No holes or signs of Fodder forcing his way out were found in a check of the enclosure.

The gazelle shared the Grasslands Africa habitat with the giraffes, zebra and waterbuck.