PS7-25. Egg Production of Lohmann Brown Hens with Split and Conventional Feeding Programs.

Abstract The aim was to evaluate egg production, albumen height and folk color egg quality of Lohmann Brown hens fed with conventional and split feeding programs: confinement and grazing systems: conventional feed with light time grazing, conventional feed on completed confinement, split feeding with light time grazing, and split feeding on completed confinement. A total of 100 birds aged 22 weeks were randomly distributed into four feeding models with three replicates of 8 or 9 hens. This work was carried out over a period of nine weeks, with hens of same genetics constitution, and biological age. Hens were fed with a standard feed formulated to meet the minimum nutrient requirement for Lohmann Brown-Classic line. The split diet was formulated adjusting the amount of calcium, phosphorus, and protein levels based on daily requirements, increasing amount of calcium at the feeding afternoon, due to its key role in eggshell formation. This feeding strategy was implemented for permanent confinement and daytime grazing group of hens with nighttime shelter in a pen. Data for laying egg production and egg quality were statistically analyzed using a model for completely randomized design, analysis of variance Tukey’s means procedure at p < 0.05. At the beginning of the laying period non-uniform egg production was observed for all models of raising hens, but as laying period progressed egg production increased. At 26 weeks of hen age, egg production stabilized between 90.48 and 97.62% of total egg production (conventional vs split feeding models; p < 0.05) until reached 30 weeks of age. This revealed similar egg laying potential of Lohmann Brown when they had access to alfalfa pasture which seems to stimulate a higher percentage of laying comparing to hens raised on floor-based pen. Eggs laid by hens fed the split feeding model (floor and grazing) had similar albumen height (9,72 mm, 9.64 mm, respectively, p > 0.05) while those laid by hens on the conventional feeding model plus grazing pasture had a lower albumen height (8.94 mm, p < 0.05). This could be evidence that split feeding systems could improve thick of albumen. The yolks of eggs laid by 30-week-old Lohmann Brown hens fed in total confinement feeding system had the less intense yolk color than grazing alfalfa pasture system. This result confirms that eggs laid by pasture-raised hens could have more intense yolk color due to the natural pigments contained in alfalfa (Medicago sativa), purslane (Portulaca oleracea) and mallow (Malva sylvestris) plants growing in the pasture grazed. Similar finding was reported by Chavarría et al. (2021) when backyard hens grazed on diverse native vegetation stand. It is concluded that split feeding system when hens grazed alfalfa pasture, optimizes productivity without affecting negatively egg quality.