怀头鲇幼鱼摄食前后消化酶活性的变化

Changes in Digestive Enzyme Activities of northern sheatfish After feeding

试验研究了摄食时间对怀头鲇幼鱼胃、肠道中蛋白酶、淀粉酶和脂肪酶活性的影响。结果表明:摄食后怀头鲇幼鱼胃蛋白酶活性下降,之后开始快速上升至摄食后3 h酶活性达到最高峰,与摄食前相比差异显著(P<0.05);而肠蛋白酶活性一直保持上升趋势,摄食后3 h酶活性达到峰值。摄食前后淀粉酶活性变化趋势明显不同,即胃中淀粉酶活性在摄食后1 h出现明显的降低(P<0.05),但该酶活性很快又迅速上升,到摄食后3 h达到最高峰;肠淀粉酶在摄食后表现为先降低后增加的趋势,摄食后5 h达到最高峰;同时发现,摄食前后胃中脂肪酶活性变化较为剧烈,摄食后3 h达到最高峰,而肠道中脂肪酶活性的变化较为缓慢,说明摄食对胃中脂肪酶活性影响较大。

The effect of feeding on the activity of protease,amylase and lipase in the main digestive organs of northern sheatfish was studied. The results showed that the activity of protease in stomach decreased after feeding,then increased and kept at a high level after 3h of feed- ing ,which was 126.40 ± 18.96 U/mg protein and presented a striking contrast to feeding ago （P 〈 0.05 ）. But the activity of protease in intestinal canal increased all along and kept at a higher level after 4h of feeding , which was 70.68 ± 9.87 U/mg protein. The effect of feeding on the activity of amylase indicated that the amylase in stomach decreased after l h of feeding（ P〈 0.05 ） ,then increased and kept at a higher level after 3h of feeding, which was 15.87 ± 2. 02 U/mg protein. Trend of amylase activities in stomach change appeared from low to high.The activity of amylase in intestinal canal kept at a higher level after 5 h of feeding. At the same time, the results showed the activity of lipase in stomach changed quite acutely, which kept at a higher level after 3 h of feeding, but the activity .of lipase in intestinal canal changed slack, The feeding effect the activity of lipase in stomach was more distinct than the activity of lipase in intestinal canal.