The consumer watchdog has been urged to crack down on Australia's big poultry suppliers for using the term 'no hormones' in their advertising because hormones have not been used in any chickens in Australia since the 1960s.

According to Sydney Morning Herald, the animal welfare group, Voiceless, has lodged a complaint with the Australian Competition and Consumer Commission alleging several of the big chicken suppliers as well as the fast-food chain, Oporto, are misleading consumers.

Voiceless said the advertising suggested that producers were "at liberty to use hormones but have chosen not to" and the chickens were grown naturally, "playing on community preference for natural products".

Voiceless said the major companies – Oporto, Steggles and La Ionica – advertised that their chickens contained 'no hormones'.

The complaint comes after the Commission launched legal action in the Federal Court against Baiada Poultry and Bartter Enterprises, which supply chickens under the Steggles brand, alleging barn-raised chickens are not 'free to roam'.

The Commission is also taking action against Turi Foods, which supplies La Ionica, and the Australian Chicken Meat Federation, which represents meat chicken breeders, growers, processors and suppliers.

The consumer group, Choice, has also been highly critical of the chicken industry's repeated claims about not using hormones.

A spokeswoman for Choice, Ingrid Just, said advertising that chicken products, including those sold in the major supermarkets, had no added hormones only added to the confusion of consumers who were already baffled by food labelling.

Ms Just said: "Chickens haven't had hormones added to them for years and years and the problem is that by using the term 'no added hormones', it suggests that any products that don't use that term are actually adding hormones."

But Andreas Dubs, the executive director of the Australian Chicken Meat Federation, said they repeatedly surveyed consumers and found 75 per cent of people still believed that hormones were added to chickens in Australia.

Mr Dubs said he suspected the myth of added hormones in chickens had resurfaced when Coles announced earlier this year that it would be the first national food retailer to no longer stock beef that contained hormone growth promoter. Unlike chicken meat, about 40 per cent of Australian beef is grown with added hormones.

Mr Dubs said the chicken meat industry was not trying to mislead consumers.

He said: "We find that even though we keep saying it, the majority of people still believe hormones are added."

A spokeswoman for Oporto said the company developed an "authentic chicken icon" in 2008, which includes the wording 'no added hormones' and was used on packaging, menu boards and the chain's web site.

She continued: "The icon was developed in response to the incorrect but continued public perception regarding the use of hormones in chicken. We have only ever sought to provide the public with accurate information on this issue."

The Sydney Morning Herald report added that a spokesman for the commission said he could not comment on complaints or investigations.