Fig. 3. (A-C) Growth trajectory of follicles during initiation of follicle growth. Oocyte diameter (A), number of GCs (B) and GC height (C) in the largest cross section on days 12 (open circles and white bars) and 21 (black circles, hatched bars); p, primordial; t, transitional; 1°, primary; 1°+, primary with a second layer forming; 2°, secondary; 2°+, secondary with third layer forming; new 1°+, primary with < five second-layer cells. Values are presented as the mean ± 95% confidence interval. *** P<0.0001, ** P<0.01 and * P<0.05: significant differences between days 12 and 21. For all three variables there was a significant difference between values at successive stages (supplementary material Table S1), except oocyte diameter between 2° to 2°+ on day 12.