吉富品系尼罗罗非鱼生长性能的选择响应分析

Selection response to growth performance of F_6～F_9 of GIFT strain Oreochromis niloticus

在流水池饲养环境里,对吉富品系尼罗罗非鱼(Oreochromis niloticus)选育系F6～F9 4代鱼生长性能进行比较。153 d的试验结果表明,F6～F9 4代鱼绝对增重率分别为1.31、1.38、1.45、1.51 g/d。其中,F9比F8提高4.14%,F8比F7提高5.07%,F7比F6提高5.34%,生长速度逐代提高的平均值为4.85%,与2004年研究得到F7比F6提高4.42%的结果相近。F6～F9 4代鱼体重变异系数分别为0.33、0.31、0.29、0.29,呈现出逐代降低的趋势。试验期间,F6～F9 4代鱼的雌鱼特定每天增重率分别为2.69%、2.73%、2.77%、2.78%,F6～F9 4代鱼雄鱼特定每天增重率分别为2.81%、2.85%、2.88%、2.90%,雌、雄鱼间差异显著(P<0.05)。F6～F9 4代鱼的生长性能比较表明,吉富品系尼罗罗非鱼选育系生长性状的选择响应约4.85%。

In 2005 F6～F9 of GIFT strain Oreochromis niloticus was compared from seedling for 153 days in concrete ponds.The average of body weight gain of F6,F7,F8,F9,were 1.31,1.38,1.45,1.51 g/d,respectively.The order of growth rate in 2005 was the same of F6,F7,F8 that checked in 2004.When neighboring generations was compared,F9 was 4.14% higher than F8,F8 was 5.07% higher than F7,F7 was 4.42% higher than F6,which was averaged 4.85%,and was close to 4.42% that checked between F7 and F6 in 2004.The specific growth rate（SGR） of female was 2.69%/d,2.73%/d,2.77%/d,2.78%/d for F6,F7,F8,F9,respectively,and SGR of male was 2.81%/d,2.85%/d,2.88%/d,2.90%/d,correspondingly.Male fish was significantly bigger than female（P0.05）.Selection response to growth performance of F6～F9 of GIFT strain Oreochromis niloticus was about 4.85%.