鲫鱼与草鱼的肠道微生物区系及主要消化酶活性研究

Studies on Intestinal Microflora and Major Digestive Enzyme Activities of Carassius auratus and Ctenopharyngodon idella

为了探明鲫鱼(Carassius auratus)和草鱼(Ctenopharyngodon idella)的肠道微生物区系及主要消化酶活性,研究两种鱼的生活习性机制,通过采集喂养时间和环境一致的草鱼和鲫鱼各5尾,无菌操作提取肠道内容物,比较分析了鱼的肠道微生物、肠道酶活性及微生物活度。结果显示:两种鱼的肠道真菌和乳酸菌的数量差异较大,草食性的草鱼肠道内真菌数量明显多于杂食性的鲫鱼,而乳酸菌的数量却呈现出相反的结果,但二者差异不显著(P>0.05)。鲫鱼肠道内的蛋白酶、纤维素酶、木聚糖酶活性高于草鱼,二者差异极显著(均P<0.01),但两种鱼的肠道淀粉酶活性则差异不显著(P>0.05)。鲫鱼的肠道微生物活度明显高于草鱼,差异极显著(P<0.01)。综上,鲫鱼和草鱼在肠道微生物及酶活性方面存在一定的差异,草食性为主的鱼肠道内真菌数目高于杂食性鱼,而乳酸菌数目低于杂食性鱼,杂食性鱼肠道内多种酶活性高于草食性鱼。

In order to explore the intestinal microflora and main digestive enzyme activities of Carassius auratus and Ctenopharyngodon idella,the life habit mechanism of the two fishes was studied.Five grass carps and five crucian carps with the same feeding time and environment were collected,and the intestinal contents were extracted by aseptic operation.The intestinal microorganisms,intestinal enzyme activities and microbial activities of the two fishes were compared and analyzed.The results showed that there were significant differences in the numbers of intestinal fungi and lactic acid bacteria between the two fishes.The number of intestinal fungi in herbivorous Ctenopharyngodon idella was significantly higher than that in omnivorous Carassius auratus,while the number of lactic acid bacteria showed the opposite result,but the difference was not significant(P>0.05).The activities of protease,cellulase and xylanase in the intestine of Carassius auratus were higher than those in Ctenopharyngodon idella,reaching the extremely significant levels(all P<0.01),but there was no significant difference in the activities of amylase between the two species(P>0.05).The intestinal microflora activity of Carassius auratus was significantly higher than that of Ctenopharyngodon idella,reaching the extremely significant levels(P<0.01).In conclusion,there are some differences between Carassius auratus and Ctenopharyngodon idella in intestinal microflora and enzyme activities.The number of fungi in the intestine of herbivorous fish is higher than that of omnivorous fish,while the number of lactic acid bacteria is lower than that of omnivorous fish,the activities of many enzymes in the intestine of omnivorous fish were higher than those of herbivorous fish.