Hanyi Shi

IntroductionBetween 15 and 20 weeks of age, layer pullets undergo rapid physiological changes, including reproductive tract maturation, ovarian follicles development, increased calcium intake for medullary bone formation, and metabolic and hormonal adjustments to support daily egg production (Xin et al., 2022; Bahry et al., 2023; Noetzold and Zuidhof, 2025). These developmental events impose highe ...