11 LOHMANN TIERZUCHT › MANAGEMENT GUIDE 11 ENVIRONMENT Environmental conditions have an effect on the well-being and performance of the birds. Important environmental factors are temperature, humidity and level of toxic gases in the air. The optimal temperature depends on the age of the birds. The following table is a guide to the correct temperature at bird level. As mentioned before, the birds behaviour is the best indicator for correct temperature. Always reduce temperature gradually, and avoid sudden changes. If the ventilation system is used to regulate temperature, take care that the necessary fresh air is supplied. Table 1: Desired Temperatures at Bird Level Dependent on Age Age Temperature °C Day 1–2 * 35–36 Day 3–4 33–34 Day 5–7 31–32 Week 2 28–29 Week 3 26–27 Week 4 22–24 FromWeek 5 18–20 * Body temperatures of 40–41 °C are the optimum for the chicks. The relative humidity inside the house should be about 60–70 %. The air quality should meet the following minimum requirements: Table 2: Minimum Air Quality Requirements O₂ over 20% CO₂ under 0.3% CO under 40ppm NH₃ under 20ppm H₂ S under 5ppm