White tiger Betty and her partner Conde became proud parents in November at Buenos Aires zoo.

The cubs are expected to begin eating meat at the age of three months and will eventually grow to more than seven feet (two metres) in length.

White tigers have been hunted almost to extinction for their prized fur and only about 200 remain, mostly in zoos.

Zoo spokeswoman Durruty said everyone was "absolutely thrilled" at the sextuplets' birth. "Giving birth to six is extremely rare," she said.

Veterinarians at the zoo said they were feeding the smaller cubs with special milk in order to control their weight.

"When there are six it is a huge burden for the mother and it is hard for all of them to survive... one of them is usually a runt and is not well fed and dies," chief veterinarian Miguel Rivolta said.

"This way the six should survive. This is work as difficult as the work the mother has to do herself."

It is the second litter for Betty and Conde, who had triplets 18 months ago.

Officials said they are planning a contest in which Argentine schoolchildren will be given the opportunity to name the cubs.

(Agencies)