Fears have been raised that old footage taken aboard a live sheep vessel nearly six years ago will be used as ammunition against the trade, despite major reform having taken place since then.
The footage, released in response to a Freedom of Information request by the RSPCA, comprises numerous videos taken by an independent observer aboard the MV Al Shuwaikh in 2018.
During the 30-day voyage out of Fremantle to Kuwait, Qatar and the United Arab Emirates, 609 sheep died.
RSPCA Australia CEO Richard Mussell said the FOI request was made in 2018.
"This outcome should be viewed as a huge win for animal welfare and the Australian public in terms of the precedent it sets, for long-overdue transparency and access to information about the notoriously secretive live export industry," he said.
"Written departmental observer reports from the voyage revealed a number of significant animal welfare concerns, including sheep suffering heat stress.
"However, the Department refused to release the video footage that was captured on board.
"Some of that footage has now - after nearly six years - finally been released to the RSPCA after years of pursuing the review of the Department's decision to refuse access via the Office of the Australian Information Commissioner, who found that the footage should be released."
Mr Mussell said it was in the public interest for Australian to "to know what happens on board live export ships and in particular, what happened on this voyage when we know that the welfare of hundreds of sheep was compromised, leading to their death".
"What's incredibly disappointing about this saga is how hard the Department fought, over nearly six years, to keep this footage in secret," he said.
"The public has a right to know what happens on board live export vessels.
"This is yet another example of the lack of transparency within Australia's live sheep export industry."
Mr Mussell said the RSPCA was reviewing the footage.
"We reiterate our call for the Albanese government to legislate an end date to live sheep export as soon as possible," he said.
But the Australian Live Exporters' Council has raised concerns that despite its age the footage will be used by animal activists to provide incorrect depictions of the current trade.
ALEC CEO Mark Harvey-Sutton said the footage isn't representative of the industry as it stands today.
"The live export industry has committed to genuine reform and has the statistics to demonstrate it," he said.
"We will be disappointed if organisations use this old footage to misrepresent the industry, especially in an attempt to further their own policy objectives of banning live sheep exports, which we know will be disastrous for Western Australian farming families and communities."
The statement accompanying the released footage from DAFF highlights that legislative changes make conditions depicted in parts of the footage illegal under current law.
"The department supports strong animal welfare standards and condemns in the strongest terms the poor animal welfare depicted in parts of this footage," it reads.
"The Australian Government's investigations into reported animal welfare incidents aboard live export vessels during this period - including this incident - directly informed significant reforms to export law, including the Australian Standards for the Export of Livestock."
Changes brought in since the voyage include the Northern Hemisphere summer moratorium, lower stocking densities, shorter allowable wool lengths, improved pen maintenance on board vessels and new standards for the monitoring of environmental data.
"Since the introduction during 2018-2020 of new standards for the export of livestock to the Middle East, including the Northern Hemisphere summer prohibition period, average mortality rates for all voyages have reduced," the DAFF statement said.
"In the three-year periods prior to and following the implementation of these changes, average mortality rates have dropped from 0.71pc to 0.18pc for sheep, and 0.12pc to 0.06pc for cattle.
"Vessel reports over the same period, including reports from Independent Observers, indicate greatly improved animal welfare outcomes."