World's fastest land mammal dies in US zoo

Sarah, a cheetah designated the world's fastest land mammal by National Geographic magazine in 2012, has died in an Ohio zoo at the age of 15.

The Cincinnati Zoo & Botanical Garden said in a statement that it had euthanised Sarah on Wednesday due to her "diminishing quality of life".

The average life span of a cheetah, the fastest land mammal, is eight to 12 years, the zoo said.

Sarah was dubbed the fastest cheetah when she ran 100 metres in 5.95 seconds, or 98.2km/h, during the filming of a National Geographic special, beating her previous world record of 6.13 seconds in 2009.

Cameras captured the record-breaking run on Sarah's first attempt as she chased a fluffy dog toy lure on a specially designed course certified by the Road Running Technical Council of USA Track & Field, the national governing body for running and walking organised sports.

That record was more than three seconds faster than human runner Usain Bolt of Jamaica, who holds the Olympic record for the same distance.

Sarah was brought to Ohio at the age of six weeks and raised by Cathryn Hilker, founder of the Zoo's Cat Ambassador Program. She was one of the first cheetah cubs to be raised with a puppy companion, named Alexa, a now-common practice intended to serve as a calming influence.

"She lived a full life and was a phenomenal ambassador for her species," said Linda Castaneda, lead trainer for the Cincinnati Zoo's Cat Ambassador Program.

Castaneda added that Sarah had a "very expressive face" that communicated what she wanted.

The population of cheetahs has shrunk to an estimated 9,000-12,000 worldwide compared with about 100,000 in 1900, zoo officials said.