Improving growth performance and caudal fin stripe pattern in selected F6-F8 generations of GIFT Nile tilapia (Oreochromis niloticus L.) using mass selection.

摘要

Genetic improvement using the mass selection method of growth performance and stripe pattern on caudal fin in selected F6, F7 and F8 generations from genetically improved farmed tilapia strain Nile tilapia was evaluated at the National Tilapia Seed Farm of Qingdao, north China. In experiment I (2003), the average of daily body-weight gain of F7 was 12.5% higher than F6, and 28.6% higher than F5 (P<0.05). In experiment II (2004), the average daily body-weight gain of F8 was 12.9% larger than F7, and 56.9% larger than F6 (P<0.05). Coefficient of variation [(SD/mean)100] of body weight of F8 decreased significantly (P<0.05) to 79.7% of F6 and 72.9% of F7, respectively, indicating that the growth became more synchronous after continuous selection. The percentage of fish with ideal vertical and parallel stripes on caudal fins in F5, F6, F7 and F8 reached 24.8%, 28.8%, 32.2% and 37.6%, respectively, significantly higher than that of the base population (17.6%) (P<0.05)..