Experiments on chickens in the 1950s led to the creation of a new breed of animals – broilers. Their main characteristic is fast mass gain and a quick growing cycle lasting around five to seven weeks. After this period of time, their mass gain and growth rate are much slower compared to the amount of food needed. Broilers’ overgrown muscles cause big stress on joints, leading to painful deformations. A chicken’s heart is often not able to support its own body mass.
Chickens are held in poultry houses with no access to outdoor and often with no windows. There are no stimuli that the birds would get in a natural environment. Stock density can be as high as 33kg per square meter, which means that there are more than 16 2-kg birds per 1 square meter, so one bird has the space of one A4 sheet of paper.
Towards the end of the life cycle, broilers are captured, packed into plastic boxes, and taken to a slaughterhouse. During catching and transport the animals often sustain even more injuries.
Broiler chicken is the most-killed land animal in the world – every year more than 50 billion chickens are killed for meat worldwide.