Table 2 Macroscopically classified reproductive stages in C. gariepinus based on maturity scale
Maturity stages | Description of maturity stages | |
|---|---|---|
Males | Females | |
I (immature) | A pair of thin thread like gonads, sexes at early stage were indistinguishable macroscopically. | A pair of thin thread-like gonads, sexes at early stage were indistinguishable macroscopically. |
II (developing) | Testes semi-transparent and flattened | Ovary reddish, smooth, small ova were hardly visible in transparent matrix of follicular cells. Ova volumes are smaller than matrix and exuded when lobes were cut and squeezed. |
III (ripening) | Testes whitish, wide and more or less flattened. No milt exuded when cut or squeezed | Ovary opaque and yellowish; small or visible in transparent matrix of follicular cells. |
IV (running ripe) | Testes with firm clear lobes less flattened. Small amount of milt present | Ovary yellowish, fully swollen with translucent yellow ova. Pre-mature ova volume larger than matrix. |
V (fully mature) | Testes with fully developed lobes. Readily produced milt when lobes were cut and squeezed. | Ovary yellowish very soft and swollen. Greenish yellow ova were visible through superficial membranes, and ova were tightly packed. Little follicular matrix was present. Ova extruded when pressure applied on vent |
VI (spent) | Testes flattened having thin lobes but milt did not extrude when cut and squeezed | Ova did not extrude from vent when pressure was applied from pectoral fin to vent. |