A fast-moving and deadly virus has claimed the life of one of Taronga Zoo's endangered Asian elephants called Tukta.
Keepers noticed the eight-year-old female was lethargic and off her food on Monday and the zoo's team of vets commenced emergency treatment for suspected elephant endotheliotropic herpesvirus.
Vet Larry Vogelnest says the disease, which can fatally affect elephants up to the age of eight, appeared to be in its early stages on Monday morning when he examined Tukta.
Despite the team's best efforts Tukta died later that afternoon.
"There is no vaccine available for this virus and at present drug treatment is effective only in one-third of cases," Dr Vogelnest said in a statement on Tuesday.
The elephant keepers at Taronga are devastated.
"Our hearts are broken by Tukta's sudden and unexpected loss," Taronga chief executive Cameron Kerr said in a statement.
"She was a much-loved member of Taronga's elephant herd who loved caring for her little brother Jai Dee."
A zoo spokesman told AAP that Jai Dee is being given preventative antiviral treatment while the other two elephants at Taronga are not susceptible because of their age.
Tukta's death will come as a blow to the breeding program designed to conserve the species.
She was the third of six elephants born in the program at Taronga. The zoo's spokesman said there were no plans as yet for a memorial or grave site for Tukta.
It is with deep sadness we share the news that Tukta, our young Asian Elephant, passed away yesterday due to a sudden and acute onset of Elephant endotheliotropic herpesvirus disease (EEHV). EEHV is present in almost all Asian Elephants both in the wild and in zoos, but only causes illness in some young elephants and when it does is almost always fatal. Tukta began showing symptoms of illness on Monday morning, and our veterinary and keeping teams worked very hard to save her. Although she fought bravely, her condition rapidly declined and she passed later in the afternoon. Tukta was nearly eight years old, and was the third calf born at Taronga Zoo Sydney as part of our commitment to the regional breeding program for this endangered species. Everyone found joy watching her experience life as a first-time big sister when her little brother Jai Dee was born, protecting him and caring for him. No doubt our Taronga herd will be mourning her loss for several days. This is an extremely sad time for all who loved and cared for her, particularly our Elephant team whom she shared a special bond with.
- Taronga Zoo statement