Australians who think they have permission to make "sexist and silly" remarks about the leader of the country should think again, Attorney-General Nicola Roxon says.
Ms Roxon said cattle company chief executive David Farley no doubt had egg on his face after comparing Prime Minister Julia Gillard to an "old cow".
The comments, reportedly made during a speech in Adelaide on Thursday, were picked up nationally.
They have been slammed on social media and by federal politicians.
Ms Roxon said voters and public figures were free to criticise government policy but political leaders should not be subject to personal attacks.
"There's no need to make these sort of sexist and silly remarks," Ms Roxon told reporters in Sydney on Saturday.
"I am concerned that people think that there is permission to make these sorts of comments about the prime minister ... in the footy parlance, play the ball, not the man."
Federal Minister for Women Julie Collins said the comments were unacceptable.
"They amount to destructive prejudices long past their use-by date in our modern, diverse society," she said in a statement on Friday.
Mr Farley was reportedly explaining his business plans for a new abattoir designed to process old cows when he made the comparison.
"So the old cows that become non-productive, instead of making a decision to either let her die in the paddock or put her in the truck, this gives us a chance to take non-productive animals off and put them through the processing system," Mr Farley reportedly said.
"So it's designed for non-productive old cows. Julia Gillard's got to watch out."
Mr Farley's comment was met with laughter.
Ms Collins said those who laughed along to Mr Farley's jibe should take a "long, hard look at themselves."
"Australians expect more of their corporate leaders," she said.
Mr Farley also suggested Australia needed a new government.
