Lighting Programs of White Layers Hens in Start Phase Production
Souza, CBedin, A. F. SGewehr, C. E
This research aimed to study the effect of light regime on performance and egg quality of white laying hens applied at the start laying phase. A total of 420 Hy line White laying hens, at 19 weeks of age were used, distributed in a completely randomized design, during 5 periods of 28 days, extending from January to June, corresponding to the age of 19 to 38 weeks of age of the birds. Three lighting programs were evaluated: continuous 16 h of light and 8 h of dark (CONT); intermittent program with two 2-min photophases equidistant at 16 h between natural light and 8 h of dark (INT) and continuous program only using decreasing natural light (LND). Feed intake (g/bird/day), egg production (%bird/day), egg weight (g), egg mass (g/bird/day), feed conversion (g/g) and egg density (g/cm3) were evaluated. Feed intake and feed conversion were higher (p<0.05) in birds submitted to the CONT program compared to the LND program, however the CONT and LND programs did not differ (p>0.05) from the INT. Egg production, egg weight, egg mass and egg density were similar (p>0.05) between programs. Intermittent program with two photophases of 2 min equidistant 16 h between natural light can be applied in light layers at the start laying phase without impairing the productive performance and eggshell quality.(AU)
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