Caging hens, away from dust and their faeces 50 years ago, dramatically improved their survival, says a caged egg farmer on the outskirts of Melbourne.

Now Brian Ahmed at Werribee is being asked to consider major upgrades that could cost millions that he said would not guarantee happier or healthier hens.

Farmers like the Ahmeds face mounting opposition to their production systems.

"We all started as free-range, then the government's Egg Board came around in the 60s and 70s saying you need to get these birds off the ground and into cages," Brian Ahmed explained at his farm.

Sorry, this audio has expired Caged-egg farmers defend practice in face of mounting opposition

"We dropped our mortality rates dramatically.

"We went from about 25 per cent mortality, down to about 3 per cent. We also saw far less disease outbreaks, because we removed the birds from their faeces and, the most important thing, and that removed the use of antibiotics and chemicals."

The intensity of this production system also lowered their costs.

An egg produced in these cages sells for 30 cents each, while free-range eggs sell for 50 to 80 cents each.

"There are a lot of people in Australia who can't afford food, and we're not compromising on animal welfare," Mr Ahmed said.

"We're making eggs affordable to every Australian family."

Rallying for a ban

For the first time in 15 years, the public is having a say on poultry welfare standards, with a draft paper attracting a record number of submissions.

At more than 100,000 submissions, it is triple the number compared to previous standards and guidelines for other livestock.

Animal Health Australia is handling the process, and public consultation closes on February 28.

GetUp! marshalled protestors in Sydney and Melbourne, where people wore chicken masks and carried banners calling for a ban on cages.

"Battery farmed hens live their whole lives in cages, never see sunlight, lose their feathers, don't have enough room for natural behaviours like stretching their wings, and have their beaks cut," GetUp's campaign director Emily Mulligan said.

The RSPCA said the public was galvanised behind banning the "barren battery cage".

Eggs are quality checked for cracks. Caged eggs sell for around 30 cents each, while free range eggs can sell for 50-80 cents. ( ABC Danielle Bonica )

"The survey found 84 per cent would like to see battery cages phased out and that outcome goes across geographical and income-based variables," senior policy officer Jed Goodfellow said.

"The science is really clear about the welfare disadvantages of the barren cage system.

"We see the hens inside these systems suffer from the highest rates of disuse osteoporosis, they have the weakest bone strength of any system, they also suffer from fatty liver disease.

"They also suffer extreme deprivation. Inside battery cages, hens can't even extend their limbs let alone express any kind of innate behaviours."

Late last year, the RSPCA told the ABC's 7.30 it found documents showing the industry was trying to influence the drafting of the new Poultry Welfare Guidelines by "colluding" with the Department of Primary Industries in NSW, the largest caged egg producing state.

Furnishing cages for hen behaviour

One option is to furnish cages with scratch pads, perches and nest boxes.

It is estimated that furnishing cages will cost $418 million, and combined with the other mandatory reforms, this will cost an extra $935 million for caged-egg farmers to install over a decade, in the Regulatory Impact Statement with the Poultry Welfare Standards and Guidelines.

Animal welfare scientist at the University of Melbourne Paul Hemsworth said furnished or enriched cages would be a better option than a bare cage, where there was less stimulation.

"I think if you look at the literature in terms of stress, physiology, behaviour and health, the furnished cage performs very very well," Mr Hemsworth said.

Sorry, this video has expired Allegations of backroom deals to keep battery hen eggs on the market ( James Thomas )

"The perches are good for bone strength; birds are highly motivated to use nest boxes.

"Birds are moderately motivated to use dust bathes.

"There's very low levels of stress, very good health, very good efficiency of production, in terms of converting feed to eggs.

"But there's a slight restriction of behaviour, with less movement and walking.

"There's some restriction on wing flapping, although they can borrow space from other birds, and also there's a reduction in preening and that is often considered a comfort behaviour."

Mr Ahmed said he was prepared to spend money on some furnishings for the cages, but said he was still in debt for the $5 million outlay he made 15 years ago, to install the current modified cages.

"Where does it stop? This code should be about animal welfare, not about farming systems," he said.

"We are to make farmers accountable for animal welfare, no matter what farming system they use."

Farming in a suburb

Curious caged hen in air conditioned shed, where light is kept at a low level during the day. ( ABC Danielle Bonica )

The Ahmeds' farm at Werribee is surrounded by housing, with only high value vegetables or intensive poultry and egg farming left in the former food bowl for Melbourne.

As a caged-egg producer he estimated he could supply the needs of 100,000 families with eggs for a year.

But if he were to remove the cages, and stock hens at the low stocking density of 1,500 birds per hectare, as preferred by "true free-range" farms, he could stock only 3,000 birds, instead of 25,000 in the current system.

"We'd be forced to close," he said.