Swathi was born in 1997 at a Mysore zoo and brought to Guwahati in 2005, Zoo DFO TejasMariswamy told The Assam Tribune.

“She was not keeping well for some time. She died around 2 am this morning,” the official said.

The average life span of a tiger varies between 14 to 16 years. “Crossing 20 years is only in exceptional cases,” the official said.

Since the last two years, Swathi was kept away from public as she was unable to move. She was being nursed at a shelter.

Symptoms of senility, corneal opacity, weight-loss and muscular atrophy were apparent in the tigress.

However, the animal was very special to the zoo as even at this age she was responding to the zoo keepers. The zoo keepers could go near to her cage to feed her and provide medicine. She had also lost her teeth.

Swathi had given birth to 11 cubs which are in different zoos across the country now. Two of her male cubs had died here.

A 26-year-old tiger, Guddu, had died at the Kanpur zoo in Uttar Pradesh in January 2014.

Prior to that, the longest surviving tiger was 24-year-old Ramu, a male tiger at the Jaipur zoo, who died of cardiac arrest in September 2010.

Zoo officials here were enthusiastically waiting to celebrate Swathi’s birthday in January next in a grand fashion. With Swathi’s death, there are only two tigers left in the zoo now.