Effect of Age and Resting on Hens Laying Eggs with Heavy or Light Shell Weight

Abstract

Three experiments using Hy-Line W36® hens studied the effect of age and resting on the eggshell quality of eggs with heavy shell weight (HSW) or light shell weight (LSW). Researchers investigated percentage shell (PS), egg weight (EW), and shell weight (SW) for their influence as well.In Experiment 1, EW significantly increased from 52 to 64 wk of age whereas SW did not change with both LSW and HSW hens. Age x shell classes interactions for SW, PS, and SG were not significant. In Experiment 2A, EW increased from 28 to 44 wk in both HSW and LSW hens with no interaction between age and shell classes. Shell weight increased and the age x shell class interaction was significant. En Experiment 2B, EW and SW increased and PS and SG decreased with age. There were no age x shell classes interactions. In Experiment 3A there was a greater increase in SW with LSW hens than with HSW hens, resulting in a significant interaction between age and shell classes. In Experiment 3B EW, SW, SP, and SG increased with age. The age x shell classes interaction was not significant. The SW of eggs from LSW hens continued to be lighter than SW from HSW hens.