Fig. 1

The morphology characteristics and dynamically number changing of germ cells within different developmental stages follicles of Alligator sinensis at different dph groups. (A) Dorsal view of PAS stained gonad of female A. sinensis from 1-dph(a), 15-dph(b), 30-dph(c), 60-dph(d), 90-dph(e), and 300-dph(f) respectively. Nest: Germ cell nest, Oog: oogonia, Pmf: primordial follicles; PF: Primordial follicle, Pre-GCs: Pre-granulosa cells; GCs: Granulosa cells, ▲: Pyriform GCs, TCs: Thecal cells, ZP: Zona pellucida, Ba: Balbiani body, Pre-VF: Pre-vitellogenic follicles. The white dotted line shows the interface between cortex and medulla of gonadal tissue. Scale bars = 100 μm(a-e) and 50 μm(f). (B) The dynamically number changing of Nest, Pmf, PF and Pre-VF within the gonad of female A. sinensis collected from 1-dph to 300-dph. The significant differences were indicated with different letters (P < 0.05), the same letter means no significant difference (P > 0.05)