饲料中添加谷胱甘肽对黄颡鱼幼鱼生长性能、体成分、血清生化指标和抗氨氮应激能力的影响

摘要

This experiment was conducted to investigate the effects of dietary glutathione on growth perform-ance, body composition, serum biochemical indices and anti-ammonia-nitrogen stress ability of juvenile yellow catfish (Pelteobagrus fulvidraco). A total of 800 juvenile yellow catfish with the mean body weight of (1.32± 0.01) g were randomly divided into 5 groups with 4 replicates per group and 40 fishes per replicate. Fish in the control group were fed a basal diet, and others in the experimental groups were fed the basal diets supplemen-ted with 100, 300, 500 and 700 mg/kg glutathione, respectively. After 56 d feeding, ammonium chloride was used to conduct an ammonia nitrogen stress test in each group. The results showed as follows:1) with the diet-ary glutathione additive amount increased, the weight gain rate, specific growth rate and protein efficiency rate increased at first but then decreased, achieving the maximum value at 300 mg/kg group, and 100 to 500 mg/kg groups were significantly higher than control group ( P<0.05);the feed conversation ratio, condi-tion factor and hepatosomatic index had no significant difference among all groups (P>0.05). 2) Compared with the control group, the whole-body crude protein content in 300 to 700 mg/kg groups and whole-body crude lipid content in 100 to 700 mg/kg groups were significantly increased ( P<0.05) . 3) Dietary glutathione had no significant effects on serum total protein, serum cholesterol and triglyceride, glucose, urea nitrogen contents and aspartate aminotransferase, alanine aminotransferase activities (P>0.05). 4) After ammonia-ni-trogen stress, the death time of juvenile yellow catfish of experimental groups was delayed than that of the con-trol group, and at 96 h, the cumulative mortality rate of juvenile yellow catfish of experimental groups was de-creased compared with the control group, and it was significantly decreased in 100 and 300 mg/kg groups ( P<0.05) . In conclusion, dietary glutathione can increase growth performance, whole-body crude protein and crude lipid contents and anti-ammonia-nitrogen stress ability. A quadratic regression analysis on specific growth rate against dietary glutathione additive amount indicated that the optimal additive amount of glutathione in the diet of juvenile yellow catfish was 357. 69 mg/kg.%本试验旨在研究饲料中添加谷胱甘肽对黄颡鱼(Pelteobagrus fulvidraco)生长性能、体成分、血清生化指标和抗氨氮应激能力的影响.选用初始体重为(1.32±0.01)g的黄颡鱼800尾,随机分为5组,每组4个重复,每个重复40尾鱼.对照组投喂基础饲料,试验组分别投喂基础饲料中添加100、300、500、700 mg/kg谷胱甘肽的试验饲料.饲养56 d后,利用氯化铵进行氨氮应激试验.结果表明:1)随着饲料中谷胱甘肽添加量的增加,黄颡鱼的增重、特定生长率和蛋白质效率呈现先升高后下降的趋势,均在添加量为300 mg/kg时达到最大值,且100~500 mg/kg组均显著高于对照组(P<0.05);各组之间的饲料系数、肥满度和肝体比差异不显著(P>0.05).2)与对照组相比,300~700 mg/kg组全鱼粗蛋白质和100~700 mg/kg组全鱼粗脂肪含量显著升高(P<0.05).3)饲料中添加谷胱甘肽对黄颡鱼血清总蛋白、胆固醇、甘油三酯、葡萄糖、尿素氮含量和谷草转氨酶、谷丙转氨酶活性均无显著影响(P>0.05).4)氨氮应激后,试验组黄颡鱼死亡时间较对照组延迟,96 h时,各试验组黄颡鱼累积死亡率均低于对照组,其中100和300 mg/kg组显著降低(P<0.05).综上所述,饲料中添加谷胱甘肽可以提高黄颡鱼幼鱼的生长性能、全鱼体粗蛋白质和粗脂肪含量及抗氨氮应激能力.利用二次回归方程拟合特定生长率和谷胱甘肽添加量,得出谷胱甘肽在黄颡鱼幼鱼饲料中的适宜添加量为357.69 mg/kg.