Figure 6. Ovarian histology and fertility of Elavl2-knockdown mice. Hematoxylin and eosin staining of ovarian sections from (A) 16-day- and (B) 10-week-old mice. Black, light gray, and dark gray arrows point on primary, secondary and tertiary (antral) oocytes, respectively. (C) Frequency of primary, secondary and tertiary (antral) oocytes in WT and TG ovaries. (D) Long-term breeding performance. Three pairs of littermates were continuously mated for 9 mo. The y-axis shows the cumulative litter size upon each litter. The x-axis represents calendar months. (E) The average litter size of WT and TG mice during 9 months of breeding.