Replacing 1,600km of one of the world's longest structures could alleviate psychological pressure on Australia's pastoralists.

Key points: The fence is more than 100 years old and stretches from Surfer's Paradise to the Great Australian Bight

The fence is more than 100 years old and stretches from Surfer's Paradise to the Great Australian Bight A SA Government-commissioned report shows wild dogs killed 19,026 sheep in 2018

A SA Government-commissioned report shows wild dogs killed 19,026 sheep in 2018 Pastoralists say dingoes and wild dogs are having an impact farmers' finances and mental health

That's according to Livestock SA president Joe Keynes after a report commissioned by the State Government showed it would cost $25 million to replace ageing parts of the fence.

The fence, which is more than 5,000km long and runs through South Australia, NSW and Queensland, was built to keep dingoes from hunting sheep in the south of the continent. It stretches from Surfer's Paradise to the Great Australian Bight.

Pastoralists and Livestock SA said with some parts of the fence being more than 100 years old, it could no longer keep the sheep safe from wild dogs and dingoes, which could be taking a toll on the finances and the mental health of pastoralists.

The dog fence stretches through South Australia, NSW and Queensland. ( ABC News: Tim Lee )

While there has been no promise of funding, Mr Keynes was confident there would be money for the fence.

"The whole report is really good it demonstrates that we need to do this work to ensure we've got a viable sheep industry in the north, but it also protects the whole of the South Australian sheep industry," Mr Keynes said.

"I'm confident that there will be some significant investment in the dog fence."

Mr Keynes said funding would likely come from the State and Federal Governments as well as the livestock industry.

The report estimated upgrading the fence would create 14 jobs in the first year, 63 in the third year and 27 in the 20th year.

Work to rebuild the fence was expected to take three years, with job creation growing for ongoing maintenance work.

The report said if the fence was not replaced, pastoralists would likely be paying four times what they were currently paying to control wild dogs by 2038, costing the industry as much as $13.9 million.

The report showed wild dogs killed 19,026 sheep in 2018 but that number was expected to climb to 26,639 at the current rate of spread.

The report said that number could be as high as 122,154 by 2038 if the rate of spread increased.

Livestock SA president Joe Keynes says an upgrade of the dog fence would be funded by government and industry. ( ABC News: Claire Campbell )

Why does the fence matter?

Mutooroo Pastoral Company managing director James Morgan said he wanted to see more action on funding.

"The dog fence has been the sleeping protector of the South Australian sheep industry," Mr Morgan said.

"I'm sure the government has their reasons for holding off but it's a very small amount of money compared to what's spent in the urban areas and we are a $1.8 billion industry."

His company runs properties on both sides of the dog fence, including Mulyungarie Station.

Mr Morgan said his employees on that station were inundated with wild dogs, having shot 360 last year, with many more killed with baits.

That compared with just 50 wild dogs shot in a normal year.

"Our staff saw [dingoes] just jumping over the fence," he said.

He estimated that property lost at least 500 sheep to wild dogs last year but said it was hard to say how many sheep had been lost to dogs and how many were lost to drought.

The dog fence which divides cattle country from sheep country in South Australia. ( ABC Rural: Lucas Forbes )

Mr Morgan said controlling dogs had cost his business up to $100,000 and was taking a toll on his employees.

"You can't rest at all when there's dogs on the property, it's a constant vigil so that's probably having an effect on our employees and everyone in the district," he said.

Dogs can put pressure on cattle too

Pastoralist Tony Williams, who runs cattle on Mount Barry Station north of Coober Pedy, just outside the fence, warned that if dogs penetrated far south into the state, it would be hard to remove them later and would have dire consequences for the sheep industry.

Pastoralists say as the drought worsens, more dingoes are heading south in search of food and water, putting them in conflict with sheep producers. ( Supplied: Invasive Animals Cooperative Research Centre )

"If the dingo or wild dog gets right into the southern country, believe me, they'll have a hard time keeping them contained," he said.

Mr Williams, who owns a property in the Flinders Ranges, said wild dogs were a significant problem in the region during the 1990s.

"When times are tough they'll pull down up to 50 sheep in a night, three or four dogs, just for the fun of it," he said.

Mr Williams said if cattle stations did not try to keep dingo numbers down, they could lose hundreds of calves.

He said wild dogs hunted livestock more in droughts due to there being less small native animals for them to hunt.

Mr Williams said he lost about 30 calves to dogs last year, despite not being in drought.

In defence of dingoes

Some ecologists said dingoes could be a benefit to cattle producers north of the fence.

Professor Corey Bradshaw from Flinders University said dingoes were an important species north of the dog fence.

"Dingos, where they're allowed to persist, can actually reduce kangaroo densities which then leaves more grass for cattle pastoralists and then the cattle increases," he said.

"So, you can actually get a higher hectare profit if you have healthy dingo populations on your property.

"We haven't really done that [research] for sheep and there might be heavier losses in some cases versus others."

Professor Bradshaw said dingoes could also help reduce the numbers of feral foxes and cats.

"So you get a lot of benefits for native marsupials that are hit pretty hard by cats and foxes," he said.