饥饿和恢复投喂不同时间对西伯利亚鲟消化酶活性的影响

Effects of Different Starvation and Refeeding Periods on Activities of Digestive Enzymes in Siberian Sturgeon Acipenser baerii

在水温18.2~21.3℃下,将初体质量(64.43±1.06)g的西伯利亚鲟Acipenser baerii饲养在室内500L流水水族箱中,对照组(S0)持续投喂35d,试验组S5、S10、S15分别饥饿5d、10d、15d后均恢复投喂20d。每个处理设3个重复,每个重复50尾鱼,研究饥饿和恢复投喂不同时间对肝和中肠淀粉酶、脂肪酶和蛋白酶活性的影响。结果表明,幼鲟饥饿5d后恢复投喂20d时,体质量接近对照组水平(P>0.05);饥饿10d或15d恢复投喂20d时,体质量显著低于对照组水平(P<0.05)。饥饿5d、10d、15d后,肠道和肝蛋白酶和脂肪酶活性降低。饥饿5d时,肠道和肝淀粉酶活性最大,随着饥饿时间的延长,活性降低。恢复投喂结束时,S15组肝蛋白酶、脂肪酶和肠道脂肪酶显著低于对照组(P<0.05),其余各组逐渐恢复至对照组水平。本试验条件下,西伯利亚鲟幼鱼消化系统消化酶活性具有部分补偿效应,随着饥饿时间的延长补偿效应逐渐降低。

Siberian sturgeon Acipenser baerii with an initial body weight of(64.43±1.06)g were reared in an indoor 500 L running aquarium,fasted for 0 d(control,continous feeding for 35 d),5 d(S5),10 d(S10)and 15 d(S15),respectively,and then refed for20 d at water temperature of 18.2~21.3℃with three replicates of each treatment to evaluate the effects of different starvation and refeeding periods on activities of amylase,lipase and protease in liver and midgut of Siberian sturgeon.It was found that the fish refed in S5 group had body weight close to the fish in control group(P>0.05),with significantly lower body weight in S10 group or S15 group than that in control group(P<0.05).There were decrease in activities of protease and lipase in intestine and liver in the fish fasted for 5 d,10 d and 15 d,with the maximal amylase activities in intestine and liver of the animals fasted for 5 days,subsequently,decreased with the prolongation of starvation time.At the end of the feeding trial,the activities of hepatic protease,lipase and intestinal lipase were still significantly lower in Siberian sturgeon in S15 group than those in control group(P<0.05),while the activities of protease,lipase and amylase in other groups gradually recovered to the level of control group.In conclusion,the digestive enzymes activities of intestine and liver showed partial compensation effect,the compensation effect being decreased gradually with the prolonging of starvation.