To offer high productivity, laying hens require optimum environmental conditions, among which proper room temperature is essential both in winter and in summer.
Ambient temperature is critical to the health, growth and usability of farm birds. For laying hens, the ambient temperature that stimulates increased metabolism is from 13°C to 18°C. In this range, the feed conversion is optimum. Furthermore, ambient temperature has a significant impact on ovulation – laying performance drops by 50% at 6°C and to zero at -4°C. At temperatures above 20°C, hens lay smaller eggs with thinner shells. At temperatures above 35°C, the risk of hen death due to hyperthermia increases drastically.
Above 25°C, each 1°C increase in temperature reduces the laying performance by 1.5%, however at ambient temperatures above 30°C, feed consumption and production drop drastically. Laying performance drops when temperature exceeds either the low or the high limit of the optimum. The risk of hyperthermia escalates in summer and in autumn, causing a two- or threefold increase in water intake. This results in an increased excretion of vitamins and minerals and a reduced count of antibodies, causing an increased susceptibility to diseases in birds.
An increase of temperature above 24°C increases the mortality rate in adult birds.
Another important aspect of coop temperature is stability. The measurements showed that the laying performance drops from 48% to 40% as the amplitude of temperatures between day and night increases from 3°C to 6°C (measured with an excess of the low limit of the optimum temperature at night).
The utmost laying performance drops occur under drastic temperature changes. A thriving laying hen farm are primarily rooms that protect the birds from direct exposure to outside climate impact. The thermal insulation materials used should prevent the coop temperature from dropping below 10°C when outside temperatures are below -15°C and from exceeding 25°C during summer heat waves. In such environment the bird uses all feed energy for egg production and not for body temperature regulation.