Description
Our study investigated the differences of uterine transcriptome in laying hen holding a high or low breaking strength shell. The eggshell calcification periods are divided into three periods, namely initiation, growth and termination periods respectively. The large differences in the transcriptome proved that the initiation period of calcification determine eggshell strength. Overall design: Examination of 3 eggshell calcification periods of hens laying hard or weak-shell respectively.