Derek Shirley, a farmer in southeast Queensland, found six of his cows, valued at $10,000, dead this week following a violent thunderstorm. The storm took place last Monday, but Shirley didn't find the cows until two days later when he went to check on them. The farmer found the animals lying in a straight line with their heads thrust between the wires of a nearby cattle fence.

"There was just a storm, it was a pretty severe storm, there were a few cracks of lightning and thunder and then there was one particularly loud one and that's all we heard," said Shirley in an interview with ABC news.

"Our first thought was that they had been poisoned, but they don't just lay in a line like that," he said. "The strike has actually thrown them into the fence, like some of them were through the wires."

Dr. Karl Kruszelnicki, a science expert with ABC, believes the cows were killed by a lightning strike; the force of which threw their bodies through the air.

"What astonishes me is their heads are all through the wire, they have been blown there and that is not something I have come across before," he said. "To do that you would need a huge blast of air, because a cow is not an insignificant beast, it is not like a cat weighing three kilograms, you're talking hundreds of kilograms."

"When water heats up and turns into steam it expands in volume by 1,700 times, that's huge," he continued. "That would have provided enough of a push to blow the cattle into and sometimes through the fence."

But while the force created by water rapidly expanding in the superheated area of a lightning strike might explain the cows' positioning, it wouldn't have actually killed them.

For that, Kruszelnicki theorized that they all died simultaneously of heart attacks.

"When the lightning hits the ground you get a spreading of an electric field," he explained. "Assuming it happened behind the cattle and they're facing into the fence, at their back legs the electric field is, we'll just have a guess, a million volts per meter and it weakens and at their front legs say half a million volts a meter. The electric field goes in through their back legs, through the body and down their front legs and in-between is the heart and they have a heart attack."

The cows' deaths would have been relatively painless according to Kruszelnicki, consisting of "brief instantaneous pain," with consciousness lasting "at the most...six seconds."

Lighting strikes fatal to cattle are not uncommon in Australia.

A lightning strike killed six of a farmer's cows in Queensland last year, in 2016 four cows were fatally struck together in Victoria, and a deadly lightning strike in 2005 claimed the lives of 68 cows in New South Wales.