DALLAS (CBSDFW.COM) – The Dallas Zoo is conducting a necropsy to try to learn more about the death of its 1-year-old giraffe, Witten.

Witten died Monday while under anesthesia during a physical exam.  He stopped breathing.

Witten the giraffe. (credit: Dallas Zoo)

The zoo said veterinarians tried to resuscitate him but were unable to.

Witten was getting prepared to move to a zoo in Canada, as part of a breeding recommendation from the Association of Zoos and Aquariums.

Witten was named after Dallas Cowboys legendary tight end Jason Witten shortly after he announced his retirement from the NFL.

Jason Witten has since returned to play for the Cowboys.