Rare white tigers

Three rare white tiger cubs have delighted visitors at the Buenos Aires zoo, tumbling in the grass of their enclosure in their first public appearance since being born late last year.

Zookeepers said the birth of the blue-eyed Bengal tiger triplets represented an important contribution to saving the animals from extinction.

"There are only about 250, not even 300, animals of this variety in captivity, so every birth in the Buenos Aires zoo contributes to saving this type of Bengal tiger," chief veterinarian Miguel Rivolta told Reuters Television.

Rivolta said the zoo's breeding record showed the tigers had exactly the right environment and diet, which includes 10kg of mutton twice a week as well as fresh poultry meat.

White tiger mother Bety gave birth to the cubs, two females and one male, on December 23 but Thursday was the first time zoo visitors were able to see them.

White tigers are a genetic variation of the better-known orange Bengal tigers.

Between 5000-7000 tigers live in the wild, down from 100,000 at the start of the 20th-century. Poaching, deforestation and over-hunting of their natural prey have hit their numbers.

"There's a big party every time there's a birthday at the zoo," Rivolta said. "It's a step forward for the conservation project."