Battery farming

Battery cages are a housing system used for various animal production methods, but primarily for egg-laying hens. The name arises from the arrangement of rows and columns of identical cages connected together, sharing common divider walls, as in the cells of a battery. Although the term is usually applied to poultry farming, similar cage systems are used for other animals. Battery cages have generated controversy between advocates for animal rights, and industrial producers.

Battery cages are the predominant form of housing for laying hens worldwide. They reduce aggression and cannibalism among hens, but are barren, restrict movement, prevent many natural behaviours, and increase rates of osteoporosis. As of 2014, approximately 95% of eggs in the U.S. were produced in battery cages. In the UK, statistics from the Department for the Environment, Food and Rural Affairs (Defra) indicate that 50% of eggs produced in the UK throughout 2010 were from cages (45% from free-range, 5% from barns). However, introduction of the European Union Council Directive 1999/74/EC which banned conventional battery cages in the EU from January 2012 for welfare reasons, means the number of eggs from battery cages in the EU states is rapidly decreasing.

Battery cages also used for mink, rabbit, chinchilla and foxes in fur farming, and most recently for the Asian palm civet for kopi luwak production of coffee.

Battery cages for sun bears reared for their bile

Battery cages for mink reared for their fur

Battery cages for silver foxes reared for their fur

Battery cages for civets reared for kopi luwak (coffee) production

Before the cage was invented, most hens were free-range.

...
Wikipedia