Eggs were collected daily, and egg weight was measured in all eggs produced the last 2 d of each of the seven 28-d periods. Feed intake was measured by rep
licate every 28 d and mortality was recorded as produced. From these data, ADFI, egg production, egg weight, egg mass, and feed conversion ratio (FCR) per kilogram and per dozen of eggs were calculated by period and cumulatively. In addition, all the hens were weighed individually at the beginning of the experiment and at the end of each of the seven 28-d laying periods, and the BW gain per replicate was calculated. The number of dirty, broken, and shell-less eggs was recorded daily by replicate. Egg quality was measured in 10 eggs collected randomly from each replicate the last day of each 28-d period. Eggs were individually weighed and broken, and albumen height, yolk color, and shell density (mg/cm2) were measured as indicated by Pérez-Bonilla et al. (2011). Shell thickness was measured in 5 eggs per replicate chosen at random at the end of each 28-d period using a digital micrometer (model IT-014UT, Mitotuyo, Kawasaki, Japan). The average of 3 measurements taken at the center of the egg was used for further evaluation.