The National Animal Welfare Advisory Committee (NAWAC) developed the new code after reviewing the 2005 code and considering scientific evidence and submissions from the public, said committee chair John Hellström.

The new code contains minimum standards and best practices that aim to encourage the highest standards of animal husbandry, care and handling. The code covers the full range of hen husbandry topics, including the provision of food and water, shelter, and protection of health. The biggest change in the new code is to require that the cages in use now can no longer be used.

From the 7 December the cages commonly referred to as “battery cages” will no longer be allowed to be installed, and existing cages will be progressively removed from use over the next 10 years.

"Battery cages house three to five hens and restrict hens from expressing a range of normal behaviours,” Dr Hellström said.

"The new code will ensure that hens live in an environment that meets their welfare needs and lets them carry out a range of normal behaviours, such as perching, pecking and scratching.”

Under the new code farmers will be able to house their hens in colony cages or barns (which may or may not give hens’ access to the outdoors).

Colony cages are an acceptable option under the code because they allow hens to display a range of normal behaviours. Colony cages are bigger, typically housing 40-60 birds, and include a secluded nesting area, perches and a scratching area.” Dr Hellström said.

The code replaces the existing 2005 code of welfare for layer hens. Click here to read it.

Battery cages house a small number of birds, usually three to five, and do not allow hens to express many of their normal behaviours. Normal behaviours include nesting, perching, scratching, pecking, and dustbathing.

Colony cages house between 20 and 90, but typically 40 to 60, hens.

About 83 per cent of New Zealand eggs are currently produced by hens housed in battery cages. Colony cages are a new housing system and have not yet been adopted by many producers.

All New Zealand’s caged eggs are produced by 47 producers. About three per cent of eggs are produced in barns and about 14 per cent are produced in barns with access to outdoors (commonly referred to as ‘free range’ eggs).

From 6 December 2012 colony cages are the only type of new cage that may be installed. Other cages will be completely banned from 31 December 2022, but many of them will be removed from use before this date. The transition will be managed in stages: