本试验旨在探讨高温季节饥饿后补偿摄食对团头鲂幼鱼生长性能、血清生化指标、肠道消化酶活性及肝脏抗氧化酶活性的影响.试验设计5个组,分别为饥饿0、5、10、15、20 d后再补偿摄食3周,依次标记为S0(对照)、S5、S10、S15、S20组.选择初始均重为(22.03±0.04)g的团头鲂幼鱼270尾,随机分入这5组,每组3个重复,每个重复18尾.结果显示:1)S10组试验鱼末体均重、增重率、特定生长率和饲料效率均达到最高,且补偿摄食期间其日摄食量和饲料效率显著高于对照组(P<0.05),说明团头鲂幼鱼补偿生长是通过提高摄食率和饲料效率共同实现的.2)S5、S10组血清甘油三酯水平显著低于其他组(P<0.05),而S20组血清谷草转氨酶活性显著高于其他组(P<0.05),说明饥饿时间过长鱼体肝脏受到一定程度损伤;血清中其他生化指标如葡萄糖、总蛋白、白蛋白、总胆固醇水平和谷丙转氨酶活性在各组间无显著差异(P>0.05).3)补偿摄食后,S15组肠道脂肪酶活性显著高于其他组(P<0.05);S20组肠道蛋白酶活性显著高于其他组(除S5组外)(P<0.05),说明饥饿时间过长在补偿摄食后鱼体内蛋白质消化能力增强.4)各饥饿后补偿摄食组肝脏超氧化物歧化酶(除S5、S20组外)和过氧化氢酶活性均显著高于对照组(P<0.05),而S20组肝脏谷胱甘肽过氧化物酶活性显著低于其他饥饿后补偿摄食组(P<0.05),说明饥饿时间过长对机体抗氧化能力的恢复有所影响.由此可见,在本试验中,高温季节团头鲂幼鱼饥饿10 d后补偿摄食3周,补偿生长效果达到最佳,鱼体免疫与抗氧化能力也得到一定增强.%A feeding trial was conducted to investigate the effects of compensatory feeding after starvation on growth performance, serum biochemical indexes, intestinal digestive enzyme activities and hepatic antioxidant enzyme activities of juvenile blunt snout bream ( Megalobrama amblycephal) in summer. Five groups were de-signed, they were hungering 0, 5, 10, 15, 20 days and then refeeding 3 weeks, which were marked as S0 ( control) , S5, S10, S15 and S20 groups, respectively. Two hundred and seventy juvenile blunt snout breams with an average body weight of (22.03±0.04) g were randomly divided into 5 groups with 3 replicates in each group and 18 fish in each replicate. The results showed as follows:1) the final fish weight, weight gain rate, specific growth rate and feed efficiency ratio were the highest in S10 group and the daily feed intake and feed efficiency ratio in S10 group were significantly increased compared with control group ( P<0.05) , which indi-cated that the compensatory growth of juvenile blunt snout breams was accomplished through increasing feeding rate and feed efficiency ratio. 2) The levels of triglycerides in S5 and S10 groups was significantly lower than that in other groups ( P<0.05);however, the activity of serum aspartate transaminase in S20 group was signif-icantly higher than that in other groups ( P<0.05) , which indicated that long-term starvation may damage the liver. No significant differences were detected among the groups in serum glucose, total protein, albumin, total cholesterol contents and alanine aminotransferase activity ( P>0.05) . 3) After compensatory feeding, the intes-tinal lipase activity in S15 group was significantly higher than that in other groups ( P<0.05) , and the intestinal protease activity in S20 group was significantly higher than that in other groups except S5 group (P<0.05), which indicated that compensatory feeding after long-term starvation may improve protein digestive ability in vi-vo. 4) The activities of hepatic superoxide dismutase ( except S5 and S20 groups) and catalase in compensato-ry feeding groups were significantly higher than those in control group ( P<0.05) , and the activity of hepatic glutathione peroxidase in S20 group was significantly lower than that in other compensatory feeding groups ( P<0.05) , which indicated that long-term starvation may repress the recovery of antioxidant capacity. It is conclu-ded that juvenile blunt snout bream after 10-day starvation and 3-week refeeding achieve the best compensatory growth effect in summer, the immune and antioxidant capacity also increase certainly in this experiment.
展开▼
