(A) Seminal vesicles, (B) epididymides, and (C) testes were carefully dissected from WT and GalNAc-4-ST1–/– male mice on the postnatal days indicated and weighed. Tissues were taken from 8, 18, 16, 14, 10, and 10 WT and 16, 19, 14, 22, 10, and 5 GalNAc-4-ST1–/– mice on postnatal days 26, 28, 30, 32, 35, and 42, respectively.