The Impact of Laying Hen Age, Egg-Laying Time, Cage Tier, and Cage Direction on Egg Quality Traits in Hens in an Enriched Cage System

This study determined the effect of layer age, egg-laying time, cage tier, and cage direction (outward-inward) on egg quality parameters of commercial layer chickens reared in enriched cages. A total of 944 layers (approximately 100 eggs every four weeks, from the 26 to the 58th week) obtained from Lohmann LSL-Classic layers reared at the Nigde Omer Halisdemir University Ayhan & Scedil;ahenk Agricultural Application and Research Centre were analyzed. Laying hen age significantly affected all the egg quality variables (p<0.01). Egg weight, shell-breaking strength, egg surface area, Haugh unit, and yolk color score differed across egg-laying time (p<0.05; p<0.01). There was variability in all the external egg quality traits among the cage tiers (p<0.05), but not for internal egg quality (p>0.05). Furthermore, it was found that cage direction had a significant effect on egg weight, shell thickness, egg surface area, and all the internal egg quality traits, except for yolk color score (p<0.05; p<0.01). In conclusion, our results highlight significant changes in egg quality traits due to layer age, egg-laying time, cage tier, and cage direction.