Effect of Cage Environmental Enrichment on Egg Quality in Two Laying Hen Strains

This study investigated the effects of environmental enrichment in cage systems on egg quality, focusing on two laying hen strains, Hyline Brown (HB) and Isa Tinted (IT). Conventional cage systems (CC) were compared with environmentally enriched cages (EEC) that included nest boxes, perches, and pecking stones. Egg quality was evaluated every eight weeks from 24 to 72 weeks of age using one randomly selected egg per cage (4 groups × 14 eggs = 56 eggs). Measured parameters included egg weight, shape index, breaking strength, shell thickness, yolk color, Haugh unit, albumen index, yolk index, and the presence of blood and meat spots. Results revealed no statistically significant differences in egg quality parameters between CC and EEC systems, suggesting that environmental enrichments alone do not influence egg quality. However, strain-specific differences were identified: HB hens produced heavier eggs with thicker and stronger shells, whereas IT hens laid eggs with darker yolks. Age-related changes in egg quality were observed in both strains, with declines in shell thickness, breaking strength, and Haugh unit over time. These findings emphasize the limited impact of cage enrichments on egg quality and highlight the significant roles of genotype and age. Further research is warranted to explore the broader implications of environmental enrichments on poultry production.