饥饿和再投喂对尼罗罗非鱼蛋白酶活性的影响

Effects of Starvation and Refeeding on Protease Activity of Oreochromis niloticus

测定了饥饿和再投喂的尼罗罗非鱼胃、肠、肝胰脏蛋白酶活性。结果表明:(1)尼罗罗非鱼蛋白酶的活性以胃为最高,肠为最低,且胃蛋白酶的活性极显著高于肠、肝胰脏(P<0.01),肠和肝胰脏之间差异不显著(P>0.05);(2)饥饿后,蛋白酶活性呈降低的趋势,饥饿处理25d后,胃、肠、肝胰脏的蛋白酶活力分别降低到饥饿处理前的42.7%、41.0%、61.5%,均与对照组差异极显著(P<0.01);(3)再投喂后,饥俄15d以内的鱼蛋白酶活性上升迅速,经过15d恢复投喂,基本上就恢复到了正常水平,且消化酶活性甚至高于一直投喂对照组,而饥饿20、25d的鱼蛋白酶活性虽缓慢上升,但仍无法恢复到正常水平,与对照组差异显著(P<0.05)。

The protease activity of stomach, intestine and hepatopancreas of Oreochromis niloticus were determined during starvation and refeeding. The results showed that among the three digestive organs, protease activity was the highest in stomach, but lowest in intestine. Protease activity in stomach was significantly higher than that in the other two organs（P〈0.01）. Protease activity in hepatopancreas was not different from that in intestine（P〉0.05）;The protease activity of stomach ,intestine and hepatopancreas decreased after 25 days, starvation, only accounting for 42.7%,41.0%,61.5% of that before starvation, significantly lower than that of the control group（P 〈0.01）;After refed for 15 days, the protease activity offish which were deprived of food in 15 days rose rapidly and some group was even higher than the control group,but had no significant change （P〉0.05）. The protease activity of fish which were deprived of food for 20 and 25 days recovered slowly but lower than the control group（P〈0.05）.