Translations:Effects of climate change on livestock/8/en

Studies of heat stress and livestock had historically focused on cattle, as they are often kept outdoors and so are immediately exposed to changes in climate. On the other hand, a little over 50% of all pork production and 70% of all poultry production worldwide originated from animals kept entirely in confined buildings even around 2006, and the raw numbers were expected to increase by 3–3.5 times for pigs, by 2–2.4 times for layer hens and 4.4–5 times for broilers. Historically, livestock in these conditions were considered less vulnerable to warming than the animals in outdoor areas due to inhabiting insulated buildings, where ventilation systems are used to control the climate and relieve the excess heat. However, in the historically cooler midlatitude regions, indoor temperatures were already higher than the outdoor temperatures even in summer, and as the increased heating exceeds these systems' specifications, confined animals are left more vulnerable to the heat than those kept outdoors.