MELBOURNE - The world's oldest sheep has died in Australia after succumbing to a record-breaking heatwave that scorched much of the country's southeast, its owner said Tuesday.

Despite her best efforts to nurse Lucky through the searing heat, owner Delrae Westgarth said the ewe died Monday aged 23 years, six months and 28 days at the farm in Victoria state where she was born.

"We brought her into the shed where she was reared and put air conditioners on her, which kept her going a bit longer, but unfortunately she didn't make the 23 years and 7 months," Westgarth told public broadcaster ABC.

Lucky was recognised by Guinness World Records as the world's oldest sheep in September 2007, then aged 21 years, five months and was something of a celebrity in her 250-person hometown of Lake Bolac, west of Melbourne.

"It's quite phenomenal, really," said local councillor Colin McKenzie of her fame.

The Polwarth-Dorchester cross was hand-raised from birth after being found abandoned by her mother, Westgarth said.

After reaching almost twice the normal top age for a sheep, which typically have a life expectancy of 10 to 12 years, Lucky failed to survive record temperatures for November, which last week soared above 30 degrees Celsius (86 Fahrenheit) last week.

Lucky was buried beneath her favourite nectarine tree, Westgarth added.