Agribusiness Elders is investigating discrepancies surrounding the valuation of cattle designated for export.
Elders also says seven senior employees in its live cattle trading division have resigned.
"Elders announces that its senior group management and board have identified certain discrepancies and issues in relation to the reporting and recognition of livestock values in its live cattle export division," Elders said in a statement on Tuesday.
Chief executive Malcolm Jackman said the company and external auditors were trying to determine if the issue was one of poor accounting, incompetency or something else.
"That's the $64,000 question, which is why the investigation is under way," he said.
"My initial belief is that it's an accounting treatment issue.... I don't think it's a physical loss issue, but that's yet to be determined."
The investigation would also try to determine the size of the problem, how long it had been going on, and why was it not picked up earlier.
"We obviously need to get to the bottom of this very, very quickly," Mr Jackman said.
Elders is still assessing the matter to determine any effect on the company's financial results for the year to September 30.
Currently, it does not believe the issue will have a material impact on the group's financial outlook.
Among those employees who have resigned is the general manager of Elders' cattle export trading division.
Mr Jackman said the employees who had resigned were based around Australia and had all resigned at once, intending to join Elders' competitor, Ruralco.
Mr Jackman said Elders did not know at this stage if there was any link between the accounting discrepancies and the intended move of the employees to Ruralco.
Elders said the employees would work their notice periods to ensure an orderly transition to a new management team.
Shares in Elders were down half a cent at 10.5 cents at 1531 AEST.