Serum estradiol measured at necropsy in the Si-deprived (n = 20 rats), Si-supplemented (n = 10) and standard rodent stock feed-fed reference (n = 10) groups. There was no significant difference between the two groups (Si-deprived vs. Si-supplemented; unpaired two-tailed Student's t-test), nor was there any association with the other measures collected (serum Si, bone length, body length, etc.).