间歇性饥饿对日本沼虾生长和几种消化酶的影响

在(25.0±1)℃范围条件下,对日本沼虾进行了不同时间的饥饿处理后再投饵的恢复生长实验。对照组连续饱食投喂18d,处理组分别饥饿2、4、8d,再分别饱食投喂16、14、10d。实验结果显示:在恢复生长时期,处理组的特殊生长率、摄食率、食物转化率明显高于对照组,胃蛋白酶、类胰蛋白酶、脂肪酶的活性变化趋势相同,均随着先饥饿再饱食的顺序先下降再上升,但脂肪酶比蛋白酶变化趋势明显;而淀粉酶的变化趋势与之相反是先上升后下降。实验结果表明,日本沼虾继饥饿后再恢复喂食出现完全或部分补偿生长效应不仅由于增加食欲,提高摄食水平,同时改善了食物转化率。因此,补偿生长是这两种生理因素共同作用的结果。

The effects of intermittent starvation on growth and some digestive enzymes in the shrimp Macrobrachium nipponense

The recovery growth experiment in the shrimp Macrobrachium nipponense was conducted following different periods of starvation.The experiment lasted for 18 days for each test group.Group C,S2,S4 and S8 were deprived of food for 0(control),2,4 and 8 days,respectively.Then each group was refed at ad libitum ration level for its rest experimental time.Upon realimentation after periods of starvation,specific growth rate,feeding rate and food conversion efficiency in terms of wet weight in each previously starved group were higher than those in group C.The change of pepsin,tryptase and lipase activity in Macrobrachium nipponense was same during starvation and after recovery growth,decreases significantly and then increases,but the trend of lipase was more evident.While the activity of amylase increases a little and then decreases significantly.The results indicated that there was completely-or-partially-compensatory effect on the recovery growth in the Macrobrachium nipponense following starvation,and that the compensatory effect mainly resulted from significant increase of the feeding level and food conversion efficiency in the recovery growth.So,the compensatory growth in the shrimp Macrobrachium nipponense is the result of the two physiological factors working together.