Not that you can see them straight away, hidden in the grass, over the hills and dales.

Or smell them. There is not even a hint of ammonia, or anything else, in the air here, on this totally free-range chicken farm.

In the paddocks across the historic Reynoldsdale property, the fat brown hens scurry through the grass, hide away in logs and luxuriate in dust baths across the 400 hectares of traditional sheep and cattle country. That equates to about 50 chickens per hectare at de Silva's farm, whereas, technically, egg farms in Australian can have as many as 10,00 chickens per hectare to still be called free-range.

"The chickens are free to do what they want here," de Silva says.

"They are not locked up at night. They live as close as possible to what they would in a natural environment. So, what would be a natural environment for a chicken? That would be at the edge of a forest. They like to look and gauge and see if there is a threat and then run back to the trees. It's like they are at home, they feel safer."

There are banks of trees and tall grass on the property that the chickens can retreat to whenever they like. The hens can also roost or lay in moveable caravans which remain open all the time.

The chickens are protected by 14 pure-white Mareema sheepdogs, each dog assigned to their own flock.

Despite the chickens wandering to and fro, very few are lost to foxes, because of the vigilance of the sheepdogs.

In one paddock, a young sheepdog Blue has a puppy's playfulness, but is still extremely wary of any likely threat. He watches over the chickens and even lets them peck at him and sit on him.

"He thinks he's a chicken," de Silva says, with a laugh. Just a chicken with a a very loud bark.

Amid all this bucolic loveliness, the chickens are producing the goods, or the eggs, under the name Hilltops Free Range.

At the prestigious Sydney Royal Easter Show last month, Hilltops snagged the champion large egg, as well as other awards including the best standard six brown eggs.

Judge Peter Gooch said the eggs were assessed according to colour, shape, shell formation and the all-important yolk, once the egg is opened.

"You want a nice raised yolk and a small air sac in the shell [which shows it is fresh] and a bright orange yolk which Hilltops certainly had, no question about that," Gooch says.

It was vindication for de Silva and his business partner, Katerina Kormusheva, both software engineers who dared to buck traditional poultry practices and start to farm totally free-range chickens only four years ago.

"It was very exciting because it was the first time we had entered the Royal Easter Show," de Silva says.

The son of a tea and rubber plantation farmer back in his home country of Sri Lanka, de Silva has been farming for 40 years as well as maintaining a successful parallel career in telecommunications software.

He decided to add the chickens to his sheep and cattle farm firstly to improve the quality of the soil in a natural way, without the application of fertiliser.

The land had been farmed for generations previously by the Reynolds family. The first cottage, dating from the early 1900s, remains on the property, old newspaper cuttings used for insulation still visible on its interior walls.

Jude de Silva has owned the property for 17 years, introducing initially 2500 free-range chickens to the farm four years ago.

What he wanted was the chicken manure to fertilise the soil, building up microbes and natural improvers such as worms, bettering the pasture for the sheep and cattle.

"I wanted to trigger a natural cycle of plant growth and carbon absorption through that process," de Silva says.

"One of the most important requirements for a plant to grow is phosphorous. If you don't have enough, the plan won't grow."

It is the chicken manure providing the phosphorous to the spoil, rather than chemical fertiliser. It's more environmentally-friendly but also cheaper, de Silva maintains. "One tonne of fertiliser can cost $800; one tonne of chicken feed costs $60," he says.

De Silva takes the pure quality of the farm seriously. The farm gates are locked and visitors are only allowed in if they wash their boots and car tyres to ensure nothing harmful gets in. The chickens don't need to be treated with chemicals either, keeping away mites through their dust baths.

Prue Merriman is the soil scientist who works on the farm. She is part of agriculture royalty in the region, the daughter of former Australian Wool Innovation chairman Wal Merriman. Her family farmed first in Murrumateman before her grandfather moved further north to Boorowa. The family developed the famous Merryville fine-wool merino sheep.

Prue Merriman, who lives in a neighbouring property to the chicken farm, says there is no doubt the chickens, combined with mulching, are making a difference to the quality of the soil.

"The paddocks that have chickens have three times the phosphorous of the paddocks that don't. It's made a huge difference," she says.

Locally, the Hilltops eggs are sold in all Woolworths supermarkets in Canberra and some IGA stores.

They are also sold direct to Canberra restaurants and cafes including the Hyatt Hotel, Teddy Picker's in Campbell, Local Press Cafe in Kingston and Red Brick Coffee in Fyshwick.

The chickens produce 20,000 eggs a day which can all be washed, put under a UV light to be disinfected and packed into a carton within an hour.

The eggs go straight into a refrigerated truck to be taken direct to the markets in Sydney or to other outlets in Canberra and the region. It's a much shorter, swifter supply chain than some of the larger-scale egg producers can manage. And the local nature of the production is important.

"People really want to know where their food is coming from," Prue Merriman says.

The Boorowa farm employs 12 people, many of whom hand-collect the eggs each day from the laying caravans.

It's a snapshot of what is a large industry in Australia.

The Egg Farmers of Australia lobby group says, on average, every Australian eats 247 eggs each year. The industry - barn-laid, free-range, caged farms - produces 19 million eggs every day to satisfy the domestic demand for the good old wholesome egg.

Egg Farmers of Australia says the industry injects $1.8 billion into the economy, with 98 per cent of egg farmers operating family-run farms.

The lobby group represents all egg farmers and has been vocal in supporting the continuation of caged hen production, saying it is essential to ensuring the supply of eggs. It also maintains production methods have evolved and "battery" hen farming - where a bird is tightly and uncomfortably enclosed in a single cage - is banned in Australia. Cage eggs are also the cheapest to produce.

Egg Farmers of Australia CEO Melinda Hashimoto says according to the CSIRO, around 40 per cent of all eggs sold in Australian supermarkets are caged.

"Therefore, it is not hard to work out that if caged eggs were suddenly removed, retailers would never have enough eggs to satisfy consumer demand and the cost of a carton eggs would skyrocket beyond affordable means," she says.

And not all-range farms are the same.

The Commonwealth Government Information Standard sets out the obligations for all egg producers when promoting or selling free range eggs. The Information Standard permits free-range eggs to be produced by hens in stocking densities of up to 10,000 birds per hectare.

The ACT Government supports a free-range standard that limits stocking densities to 1500 birds per hectare or less, and "recommends consumers purchase free range eggs produced at this stocking density or less". Still far more than the 50 birds per hectare on de Silva's farm.

De Silva, who migrated to Australian in 1978, has worked in telecommunications for organisations from ITV in London to the United Nations, helping to extend telecommunications systems across the ASEAN countries.

He and Katerina Kormusheva are applying their IT knowledge to the farm, including developing an app to produce a real-time picture of the farm.

"We are adapting an app we built for inventorising telecom towers and antennas, and it captures the geo-location of the phone and additional data,' Kormusheva says.

"For Hilltops, this data is egg numbers - from each flock, in each paddock. The location parameters of the paddocks are already captured, and also additional information on water levels, soil composition, through sensors put in the ground, and the level of feed. This will then give an almost real-time picture of the farm, the production and the soil health."

And it doesn't end there. The latest delivery to the farm is an industrial-scale pasta maker.

"There's a lot of broken eggs, so we thought a good way of using them would be to make egg pasta," de Silva says.

Bigger plans down the track include possibly an on-farm cafe.

De Silva says his farm is a work in progress. He has seen pasture growth improve with the chickens, so much so he can sell the excess as hay. And the chickens are no longer just tools for soil improvement, their eggs providing another important income stream.

The key to everything is sustainability.

"We need to care for the land and work with the land," he says.