About the length and width of a fully grown female breeding pig, stalls restrict the sow from turning around or leaving, and separate them from other potentially aggressive sows.

According to The Age, the Australian Competition and Consumer Commission and Australian Pork Limited are saying little on the watchdog's investigation of claims of being sow-stall free.

NSW Animal Liberation executive director Mark Pearson said supermarket chains Coles and Woolworths would not accept sows being in a stall any longer than 24 hours.

Australian Pork chief executive Andrew Spencer said consumers did not accept highly confining stalls, and the industry had spent millions of dollars in researching better methods, such as loose housing arrangements.

He said the pork industry standard allowed sows to go into stalls for five days after mating, while Coles allowed one day.

Phasing out was voluntary, but Mr Pearson was confident the industry would be sow-stall-free by 2017.

Animal liberationists say their video footage of piggeries is reforming the industry. Mr Pearson said the images had informed consumers, who in turn had influenced supermarkets, which were setting new standards for producers. ''They don't want to be connected with such extreme confinement and cruelty, which has been systemic within the industry.

''The pig industry is still behind the eight ball and has to be very careful in claiming things, and then it transpires that, in fact, they are not living up to sow-stall free.''

But Mr Spencer said people were not duped by selectively edited videos taken in the middle of night, alarming pigs such as an intruder would, breaking into a person's bedroom.

He said the sharp rise in illegal raids on piggeries since 2012 posed the biggest threat to biosecurity and therefore the welfare of pigs.

''The industry is changing because we recognise the consumers are dictating that we are a success or not as an industry,'' he said.

''We need to do things consumers would like to think is happening in the production of their food, and in their pork in particular.''

Mr Spencer said many producers did not want to make the reinvestment to change their housing systems, because it did not make financial sense for them.

However, Mr Pearson said economic decisions would never justify being cruel to animals.

''Veterinary science is very strong on that now, so no longer can you say it is just a dumb farm animal, or a dumb sheep or a dumb pig or whatever. Intelligence is not the measure, it is the capacity to suffer.''

Mr Spencer said the argument was philosophical.

''We are about cruelty-free production of pork; they're about [a belief] people shouldn't eat meat, shouldn't exploit animals in any way.''