The Holstein heifer, Lighting Ridge-CMD Jedi Gigi-Imp-Et, or Gigi for short, was sold for $251,000 on Wednesday night at the World Wide Sires Evolution sale at Tatura Park, near Shepparton.

"I've been pinching myself ever since," said owner Declan Patten, of Sale-based company Lightning Ridge Holsteins.

"It's been an incredible 24 hours."

The next highest price paid for a dairy calf in Australasia was $112,000, also sold by Mr Patten in 2015.

He said the aim was to breed cows that were more efficient by producing more milk while being fed the same amount as ordinary ones.

"We're trying to make a more profitable cow," he said. "It's also better for the environment."

Mr Patten, who shares his time living between Sale in Gippsland and Illinois in the US, said he hoped the Australian sale would help promote more investment in the country's cattle genetic industry.

He bought four cattle embryos, including the Gigi, from a US company for $20,000.

Gigi ranked fourth in the world Genetic Total Performance Index out of more than a million calves.

Her sister Yahoo, which ranked second in Australia in the Genetic Total Performance Index, sold for $37,000 to an Australian breeder.

Mr Patten plans to breed and sell the remaining embryos.

"It's been a great return on investment," he said.

American company ST Genetics,  who bought Gigi, hope to transport her back to the US.

Mr Patten said he came up with Gigi's name after watching too many episodes of the Real Housewives of Beverly Hills.

Gigi was the highest selling lot at the International Dairy Week auction which saw 32 more heifers sold at an average price of $14,760.