Levels of prepregnancy sex hormones in different breeds of minipigs at 8, 10, and 12 mo of age. All values (mean ± SEM) were calculated monthly. Significant differences between Tibet (n = 8 per group) compared with Bama (n = 8 per group; +, P < 0.05; ++, P < 0.005), Tibet compared with Wuzhishan (n = 8 [8 mo], 9 [10 mo], and 9 [12 mo]; #, P < 0.05; ##, P < 0.005), and Bama compared with Wuzhishan ($, P < 0.05; $$, P < 0.005) are indicated.