Table 1 Oocyte development stages of forkbeard, Phycis phycis
From: Reproductive strategy of forkbeard, Phycis phycis, from the Portuguese coast
Oocyte development stage | Description | Diameter (μm) |
|---|---|---|
Primary growth (PG) | Polyhedral with a large nucleus, where several nucleoli can easily be observed | 22.1–94.7 (59.0 ± 14.8) |
Cortical alveolar (CA) | Cortical alveoli and lipids appear in the cytoplasm | 94.16–191.5 (113.7 ± 14.0) |
Primary vitellogenic (Vtg1) | Appearance of small granules of yolk around the nucleus | 119.4–247.1 (160.3 ± 22.3) |
Secondary vitellogenic (Vtg2) | Larger yolk globules throughout the cytoplasm | 183.1–283.3 (219.2 ± 20.8) |
Tertiary vitellogenic (Vtg3) | Large yolk globules fill the cytoplasm; oil droplets surround the nucleus | 243.3–402.0 (331.0 ± 34.6) |
Germinal vesicle migration (GVM) | Germinal vesicle migrates to animal pole | 372.3–526.2 (435.1 ± 35.9) |
Germinal vesicle breakdown and yolk coalescence (GVBD & YC) | Germinal vesicle membrane breaks down; yolk globules become hydrated | 416.4–637.0 (510.8 ± 56.2) |
Hydrated (H) | Homogeneous appearance; oocytes ready to be released | 544.0–802.3 (639.0 ± 44.5) |