Two-stage multiple-color lighting spectra for optimized juvenile poultry production

A method for providing system light in a poultry residence, the method comprising providing the system light with a light generating system;

• wherein the light generating system is configured to generate system light having a controllable spectral power distribution and intensity, wherein the light generating system is configured to generate during a first time period P1, a first spectral power distribution E1, and during a second time period P2, later in time than the first period P1, a second spectral power distribution E2, wherein:
• the controllable spectral power distribution comprises (a) a first spectral range Λ1 having one or more wavelengths in the blue, and having a primary first spectral power SP(P1, Λ1) during the first time period P1 and a secondary first spectral power SP(P2, Λ1) during the second time period P2, (b) a second spectral range Λ2 having one or more wavelengths in the green, and having a primary second spectral power SP(P1, Λ2) during the first time period P1 and a secondary second spectral power SP(P2, Λ2) during the second time period P2, and (c) an amber-red spectral range Λ34 having one or more wavelengths in the amber-red, and having a primary amber-red spectral power SP(P1, Λ34) during the first time period P1 and a secondary amber-red spectral power SP(P2, Λ34) during the second time period P2;
• the first spectral power distribution E1 comprises the primary first spectral power SP(P1, Λ1), the primary second spectral power SP(P1, Λ2), and the primary amber-red spectral power SP(P1, Λ34);
• the second spectral power distribution E2 comprises the secondary first spectral power SP(P2, Λ1), the secondary second spectral power SP(P2, Λ2), and the secondary amber-red spectral power SP(P2, Λ34);
• the first period P1 is selected from the range of at least part of a day;
• the second period P2 is selected from the range of at least part of a day;
• SP(P1, Λ1)>0 Watt, SP(P1, Λ2)>0 Watt, and SP(P1, Λ34)>0 Watt;
• SP(P2, Λ1)>0 Watt, and SP(P2, Λ2)>0 Watt;
• SP(P2, Λ2)/SP(P2, Λ1)<SP(P1, Λ2)/SP(P1, Λ1);
• SP(P2, Λ34)/SP(P2, Λ1)<SP(P1, Λ34)/SP(P1, Λ1);
• SP(P2, Λ34)/SP(P2, Λ2)<SP(P1, Λ34)/SP(P1, Λ2),
• the light generating system is further configured to provide during a first rearing period RP1 selected from the range of 5-20 days, each day during the first time period P1 system light with the first spectral power distribution E1, and subsequently during a second rearing period RP2 selected from the range of at least 10 days, each day during the second time period P2 system light with the second spectral power distribution E2;
• the light generating system comprising one or more light generating device configured to generate the system light;
• and
• the light generating system comprising a control system, configured to control the controllable spectral power distribution and intensity of the system light.