What Are Cage Eggs?
Cage eggs make up 40 percent of supermarket egg purchases in Australia. Cage eggs are produced from hens that are housed in cages inside large, climate controlled sheds. The modern structures used in Australia generally have multiple tiers, with a conveyor belt between each level to catch and remove manure automatically.
What Are Cage Eggs and How Are They Produced?
Cage egg farming began about 50 years ago in response to fast-growing demand for eggs and the need to lower the unacceptably high disease and mortality rates in free range hens. Moving hens indoors not only protected them from the elements and potential predators, but also parasites and disease causing pathogens like avian influenza.
The cages that house hens have been upgraded a number of times in the decades since then and the modern cage farming system used today is clean, automated and highly efficient. Modern sheds include automated feeding, watering, climate control kept at 23°C, ventilation, lighting, and manure and egg collection. This highly efficient system enables farmers to optimise conditions for the health of the birds and produce eggs at a relatively low cost.
The Model Code of Practice for the Welfare of Animals stipulates that the minimum space allowance per hen in a cage farming system is 550cm2 per bird, though the average cage size ranges from 1800cm2 to 11,000cm2. There must be a 10cm feeder space and a minimum cage height of 40cm.
Cage hens are sometimes referred to as battery hens because the parallel rows inside sheds look a bit like rows of cells inside a battery. Cage egg farming has attracted its fair share of controversy over the years, partly due to the confinement of hens within the cages, but also because of a lot of misinformation around lighting, mortalities, hygiene and diet.
Want to see a cage egg farm for yourself? Australian Eggs invites you to take an inside look at a cage egg farm in the video below.
The advantages and disadvantages of Cage Egg Farming
Every egg production system in Australia, whether cage, free range, or barn-laid, has its advantages and disadvantages and there are trade-offs between different and sometimes conflicting measures of animal welfare. For example, increased freedom for hens to exhibit natural behaviours can expose them to greater risks in outdoor environments.
Some of the benefits and disadvantages of cage egg farming include:
|Hens rarely get sick and have lower rates of mortality due to the controlled cage environment. It’s also easier for farmers to identify and treat sick hens as they are housed in smaller groups.||Hens in cage systems have reduced social interaction with other hens.|
|Cage hens avoid injury from in-fighting within the flock as smaller groups of five or six per cage means the birds are able to establish a stable pecking order.||Cage hens are unable to roam and explore as they are confined to a relatively small space.|
|Cage eggs have a lower carbon footprint than free range eggs.||In most cage farms, the hens are unable to practice some natural behaviours like nesting and dust-bathing.|
|There is less need for veterinary medications, particularly antibiotics, in cage systems.||Cage hens are generally unable to perch, which leads to lower bone strength.|
|Cage hens are protected from predators such as foxes, feral cats and birds of prey.|
|Cage hens produce more eggs and cleaner eggs, which is why they are cheaper at the supermarket.|
There are fewer occurrences of manure-borne diseases, parasites and other exotic diseases.
While egg farmers use three main farming systems to manage animal welfare, research consistently shows the biggest factor influencing welfare is the quality of farm management and how the hen is cared for.
Some of the images of cage egg farming on the internet show hens in awful living conditions but most of the photos are decades old and many are not from Australian farms. The Australian egg industry has invested half a billion dollars in upgrading the design of cages over the last two decades to improve hen living conditions.
Are Cage Eggs Less Nutritious?
Eggs have one of the highest nutrient-to-kilojoule ratios of any food source, containing a high percentage of vitamins and minerals. Importantly, the nutritional value of eggs remains consistent, regardless of whether they are cage, barn-laid, or free range as all hens are fed a grain-based diet.
Cage eggs are the cleanest of the three farming systems as the cages tilt gently backwards so the eggs roll away onto an automatic belt as soon as they are laid. This reduces the need for egg washing and sanitisation.