MSI2 expression in single vs. double dominant follicles and its role in Mongolian sheep fecundity - Hao Qinqin; Li Penghui; Zhou Xin; He Yang; Liu Haodong; Li Xiaolong; Yu Mingyang; Zhang Zelin; Fan Jiaxin; Yang Wenchao; Yin Junzhe; Cao Guifang; et al. (Animal Reproduction Science, 2026)