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Shasta VI, a cougar at the Houston Zoo and the live mascot for the University of Houston, was euthanized Thursday after suffering from a progressive spinal disease that had rapidly deteriorated. He was 11.

In addition to his spinal disease, Shasta was found to have declining kidney function, which is common in older felines. The zoo stated that the decision to euthanize Shasta came after a comprehensive assessment of his overall wellbeing, "when it became clear that he would not recover."

Shasta VI was adopted by the Houston Zoo in December of 2011 after he and his two brothers were rescued in Washington state. Their mother had been illegally killed by a hunter, and the cubs had little chance of survival in the wild. In March of 2012, Shasta was introduced as the University of Houston's official mascot, becoming the sixth live mascot in school history and the first live male.

"With the help of the Houston Zoo, it was our honor at the UH Alumni Association to bring Shasta VI to the UH family," read a statement by Mike Pede, the school's associate vice president for alumni relations. "Shasta's service and symbolism of pride and school spirit will live on with all who went to see him, had their rings guarded by him or saw his handlers adorn his habitat with spirited notes of support. Rest easy good friend."

Shasta became central to multiple traditions at the school, making live appearances at Houston Cougars football games via webcam while also guarding the rings of graduating classes prior to fall and spring commencements. At the zoo, Shasta was known to take a perch at the top of the habitat, where he enjoyed a panoramic view of other species and seemed to pay particular attention to the elephants.

Shasta VI had brought back a tradition of live cougar mascots at the University of Houston, which had employed five total from 1947 to 1989. In-between the death of Shasta V in 1989 and Shasta VI's christening in 2012, the tradition had been carried on by students in costume.