According to Mystery Over Death of Australia’s First Cloned Sheep, Australia’s first cloned sheep died, and no one knows why:
Australia’s first cloned sheep has died despite being in apparent good health, but any chance of getting to the root of the mysterious death was lost when its decomposing carcass was cremated.
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An autopsy failed to find any reason for the ewe’s abrupt death and the carcass was cremated because it had decomposed after lying out in the open in hot summer conditions.“She was very healthy, and very sprightly…on the day she died,” Lewis told Reuters.
“There was nothing that was grossly obvious in the organs and outer body. The body’s been cremated because it was in a very bad state. To be quite honest, it was clearly pongy (smelly), very pongy.”
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Matilda was created by technology similar to that which produced Dolly, the world’s first cloned sheep, in Scotland. Lewis said he did not believe premature aging — an affliction which affected Dolly — lay behind Matilda’s demise.