SYDNEY, Feb. 15 (Xinhua) -- Australian Prime Minister Scott Morrison visited the country's flood affected northeast on Friday where hundreds of thousands of livestock have perished after two weeks of record rainfall.

While the waters have now mostly receded, an estimated 500,000 cows have been killed and their carcasses are now posing a high risk of spreading botulism and Q fever to local water supplies.

Landowners have begun an extensive cleanup effort to dispose of the dead animals, at the same time as trying feed surviving livestock which in some cases are inaccessible other than by air.

Speaking to reporters in the state of Queensland, Morrison provided words of encouragement to the communities there whom he said may take up to a decade to recover.

"This will be again one of the most prosperous regions of the country - we are going to rebuild the cattle industry here," he said.

"We've been knocked off our feet here a bit, right across the region, but we all get back up together."

Michael Guerin, chief executive of farming advocacy group AgForce Queensland, said that it was devastating to see a region which has suffered so much from drought now so deeply affected by flooding.

"The speed and intensity of the unfolding tragedy makes it hard to believe that it's just a week since farmers' elation at receiving the first decent rains in five years turned to horror at the devastating and unprecedented flood that quickly followed," Guerin said.

The Queensland government has announced a range of relief efforts including 100 million U.S. dollars in aid as well as ongoing support for farmers and their families as they recover from this once in a lifetime event.