刀鲚和湖鲚幼鱼生长代谢及肌肉脂肪酸的差异分析

为研究鲚鱼幼鱼的机体代谢与营养情况，以长江刀鲚（Coilia nasus）和湖鲚（Coilia nasus taihuensis） 幼鱼为研究对象，通过测定幼鱼形体指标，消化酶的活力和含量以及肌肉基本营养成分和脂肪酸成分，比较其生长性能和肌肉脂肪酸成分的差异，评价其营养价值并探讨生态习性差异对其造成的影响。结果表明：（1）刀鲚幼鱼胃蛋白酶和淀粉酶活力比湖鲚幼鱼的低，脂肪酶活力是湖鲚幼鱼脂肪酶活力的3倍，肝脏内未累积过多的脂质过氧化物有害物质。（2）刀鲚幼鱼肌肉中粗脂肪含量比例达到16.13%，是湖鲚幼鱼肌肉中粗脂肪含量比例的1.5倍，粗蛋白含量则显著低于湖鲚幼鱼（P〈0.05）。（3）刀鲚幼鱼肌肉中检测出21种脂肪酸，湖鲚幼鱼肌肉中检测出17种脂肪酸，湖鲚幼鱼体内没有检测出C22∶1、C24∶1、C20∶3n-6和C20∶4n-6脂肪酸。湖鲚幼鱼肌肉中的∑n-3、∑n-6以及∑n-6/∑n-3比例都比刀鲚幼鱼的高，但是脂肪酸中二十碳五烯酸（EPA）与二十二碳六烯酸（DHA）的总量比例显著低于刀鲚幼鱼（P〈0.05）。

Analysis on the difference of growth, metabolism and fatty acid in muscle between Coilia nasus and Coilia nasus taihuensis juveniles

This study was carried out to compare the fish body indicators, content and activity of digestive enzyme, basic nutrition and fatty acids components in the muscle of juvenile Coilia nasus and Coilia nasus taihuensis samples which were collected from the Yangtze River and Taihu lake, respectively. The nutrition value of the two species of Coilia and the effects of different ecological habitats were also evaluated. The results showed that：（1）The activity of digestive enzyme of C. nasuswas lower than that of C. nasus taihuensis , however , the difference was on the lipase activity of C. nasus which was 3 times higher than C. nasus taihuensis. Lipid peroxides which is harmful substances was not accumulated to large amount in C. nasus. （2） Crude fat content in C. nasus was 16.13%, which was 1.5 times higher than C. nasus taihuensis while crude protein was lower in C. nasus taihuensis. （3） There were 21 kinds of fatty acid components in juvenile C. nasus while only 17 in C. nasus taihuensis. The C22∶1, C24∶1, C20∶3n-6 and C20∶4n-6 fatty acids in the C. nasus taihuensis were not detected. Contents of ∑n-3, ∑n-6 and ∑n-6/∑n-3 in muscle of C. nasus taihuensis was higher than that of C.nasus, but content of EPA and DHA were significantly lower than those of C.nasus.