How many chickens do you put in a cage? And why aren’t the chickens in a cage?

Broilers are not raised in cages. They never have been, except for a few experiments in socialist countries. Because of their weight, chickens reared in cages may develop leg and foot injuries. Instead, they are reared on the ground, on soft wood shavings, from the first day of life. Before each arrival of chicks, the shed is washed, disinfected and supplied with new shavings.
Laying hens on the other hand, due to their much lighter weight, are better adapted to being kept in cages. In addition, the cage greatly facilitates the mechanisation of egg collection and has therefore become the most common method of rearing laying hens. However, since the year 2000, an awareness (or an awareness campaign) of the living conditions of laying hens has favoured floor rearing, which today represents the majority of farms in Europe.
Cages for laying hens – according to European regulations – must have a minimum space of 750 square centimetres divided between the area the bird can use (600 square centimetres) and accessories such as nest and litter. Cages must be equipped with perches that must provide at least 15 cm of space for each hen.