sup1.pdf

Supplementary information 1. Photomicrograph of intact ovarian tissue from beluga sturgeon at different stages of gonadal developmental. A1: perinucleolar (PN) well-ordered ovarian folds; A2: oil droplet (OD) small visible whitish oocyte; A3: primary yolk (PY) bright clear to yellow appearance; A4: secondary yolk (SY) large dark oocytes; A5: tertiary yolk (TY) fully grown black oocytes, A6: atretic oocytes presenting like empty follicles and changing the structure (Red scale bar represents 1 mm). Abbreviations: Ao: atretic oocyte; OD: Oil droplet oocyte, PY: primary yolk oocyte.