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5-Animals: US scientists euthanize cloned baby banteng



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TITLE:  US scientists euthanize cloned baby banteng
SOURCE: Reuters, by Maggie Fox
DATE:   Apr 11, 2003

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US scientists euthanize cloned baby banteng

WASHINGTON - One of a pair of cloned bantengs, a rare species of Asian
cattle, has been euthanized because it was abnormally large, its creators
said.

The banteng calf was born twice the normal size, a common cause of death
in cloned animals, said Dr. Robert Lanza of Massachusetts-based Advanced
Cell Technologies.

"The second animal we euthanized yesterday," Lanza said in a telephone
interview. "A banteng should only be 40 pounds (20 kg). The first calf
weighed 40 pounds (20 kg) but the second was 80 pounds (36 kg), almost
twice what is normal."

Despite this, the larger calf looked healthy at first. "It was snuggling
and then it took a nosedive. The vets at the zoo decided for humane
reasons that it should be euthanized," he said.

The two bantengs were cloned from the San Diego Zoo's "frozen zoo," a
project launched before anyone knew whether cloning would work. Bantengs,
enormous cattle that once thrived in the dense forests of Indonesia,
Myanmar, Malaysia and elsewhere in southeast Asia, are now endangered.

The zoo, working with cloning leader ACT, hoped to resurrect a male that
died in 1980 without ever breeding. They want to use his genes to breathe
new life into the inbred gene pool of captive bantengs, Lanza said.

The experiment, a collaboration including ACT, the San Diego Zoo, Iowa
State University and Trans Ova Genetics, worked in part because bantengs
are closely related to domestic cattle, said Lanza. They cloned frozen
cells from the long-dead banteng using cow eggs, and used a domestic cow
as the surrogate mother.

Cloning is fraught with problems and Lanza said the calf's abnormalities
did not come as a surprise.

"You don't ever know with cloned animals - the first few days are
crucial," Lanza said.

The process of cloning can lead to an abnormal placenta - the organ that
nourishes a developing embryo and fetus. Many cloned animals have been
born large, and this in turn can lead to fatal heart conditions and
failures of other organs.

"It not uncommon at all in cloning. It is called large calf syndrome,"
said Lanza.

It is also one of the reasons that most cloning experts are reluctant to
ever try cloning a human being.

Wildlife groups have spoken out against the experiment, saying the best
way to preserve a species is to save or resurrect its environment and
allow breeding populations to re-establish.

"Until the threats that caused a species to become endangered in the
first place - poaching, habitat loss, loss of prey base - are addressed,
creating animals in the lab doesn't solve the problem," said Jan
Vertefeuille, a spokeswoman for the World Wildlife Fund.

But Lanza said this was not the intention of the zoo, which wanted to
preserve captive populations of bantengs. "The goal here wasn't to get a
clone per se but to get the genes back into the population," he said.