The vast majority of commercial egg production around the world continues to be in traditional cage housing, according to the latest statistics reported by the International Egg Commission (IEC) and released by the United Egg Producers, America's largest cooperative of egg farmers nationwide.

Approximately 85 per cent of eggs worldwide are produced in traditional cages, according to the IEC report. Thirty of the 35 countries which the IEC surveyed had more than half of their eggs produced in modern cages, and 15 of the 35 countries produced more than 90 percent of their eggs in cages. Seven countries produce all of their eggs in cages, according to the report, including Mexico, China, Brazil, India, Turkey, United Arab Emirates and Iran. These countries would be in an ideal position to profit by increasing their export of eggs to the United States if egg cage housing restrictions are enacted here, as some animal rights activist groups have proposed. The United States produces 95 per cent of its eggs in modern cage housing, and only five per cent in cage-free or other non-cage type systems.

Gene Gregory, president of United Egg Producers, says that despite pressure and bullying tactics by some animal rights groups, the overwhelming majority of American consumers continue to prefer regular eggs from modern cage housing systems rather than cage-free. He said: "Americans vote every day with their wallets, and regular eggs from modern cage housing systems win every time by a landslide ratio of 95 per cent."

Cage housing systems, in which small groups of about six hens live together in a manner that allows farmers to systematically provide them with fresh feed and water and their eggs to be collected quickly for the freshest and most safe eggs, are considered by many animal health experts to be the best production system for hens.

Hens in modern cage housing systems tend to have fewer diseases, less mortality, require fewer medications, produce the cleanest and best quality eggs, with the smallest carbon footprint, and at least cost for consumers, according to Craig Reed, former deputy administrator of the Food Safety Inspection Service of US Department of Agriculture (USDA).

He explained: "The advantage of having an egg produced in a cage system is that the egg gets away from the manure, the bedding and the live animal (it rolls out of the cage after being laid) more rapidly.

"The sooner you can isolate that egg so it can be washed, cleaned, sanitised and checked for any deformities, the better that egg is going to be. And the safer that egg is going to be."

A new study by a team of researchers at the US Department of Agriculture's Egg Safety and Quality Research Unit showed there is no substantial quality difference between specialty (cage-free, etc.) and traditionally-produced eggs.

A study in 2010 by D.C. Lay, Jr., with the Agricultural Research Service of USDA, and 10 other animal welfare and behaviour experts reported that "mortality can reach unacceptably high levels in non-cage systems", "hens in conventional cages and furnished cages have less footpad dermatitis and bumblefoot" and "non-cage and outdoor systems provide a greater opportunity for disease and parasites".

In the US, the average advertised price for Grade A regular eggs from such traditional cage housing systems is 87 cents per dozen for the week of 22 October 2010, according to USDA. During the same period, cage-free eggs were $2.62 per dozen and organic (free range) were $4.06 per dozen.

The US is the fifth highest per capita consumer of eggs in the world, at 246 eggs per person each year, according to the IEC. Mexico is the highest per-capita consumer of eggs, at 355 eggs per person each year, followed by China, Japan and the Czech Republic.