Auckland Zoo's Sumatran tiger Jaka put down, just shy of his 18th birthday
Auckland Zoo's Sumatran tiger Jaka has been put down after vets found a large inoperable tumour in his intestine.
The 17-year-old tiger had been unwell for the past few weeks, sparking concern, Auckland Zoo senior vet manager James Chatterton said.
Keepers noticed Jaka had been losing weight despite having an increased appetite, and blood tests taken last week showed abnormalities, he said.
Veterinary Services Group radiologists joined zoo vets to carry out an ultrasound of Jaka's abdomen on Friday morning, revealing the tumour.
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The tumour had begun to spread throughout his body and there was no treatment that could have helped, Chatterton said.
"Euthanising Jaka was absolutely the kindest and only right thing to do."
Chatterton said Jaka would not have been feeling too unwell at this stage, just a little more tired than usual.
"We all feel really privileged that we were able to step in and put him to sleep before he felt really unwell or was in any pain," he said.
Auckland Zoo's carnivore team leader Lauren Booth said Jaka was a "very relaxed" tiger, who was "very vocal, extremely curious and very motivated by food".
He was affectionately known as the zoo's "Christmas tiger" because of his love of nutmeg and clove, Booth said.
"We keepers all loved that he had very strong tiger behaviours, and a marvellous call that we liked to refer to as his singing voice when he was communicating with his sister Molek, who he would often call to."
In August 2015, zoo vets put the 126kg cat under general anaesthetic to determine the cause of a sore paw.
Vets found Jaka had a bone lesion, similar to arthritis in an "older gentleman", Chatterton said at the time.
Jaka was born at Wellington Zoo in 2000. He was moved to Hamilton Zoo in 2005 where he fathered some cubs, before coming to Auckland Zoo in 2013.
Two of Jaka's family members remain at the zoo, sister Molek and her son, 9-year-old Berani.
Sumatran tigers are critically endangered, with only about 400 left in the wild.
They are the smallest of the six tiger sub-species, and can live for 15-20 years in the wild and up to 26 years in captivity.