摄食不同喹乙醇水平饲料的鲤鱼肠道菌群的变化

Changes of quantity and conformation of microflora in the intestine of carp cyprynus carpio fed with feed containing different concentrations of olaquindox

本文研究了饲料中不同水平喹乙醇对鲤鱼肠道菌群数量及组成的影响。设计 6组不同喹乙醇含量的饲料 (0、 2 0 0、 40 0、80 0、 1 60 0和 32 0 0mg/kg) ,对鲤鱼进行 84d的饲养试验。试验结束时 ,各组随机取 2尾鱼 ,分别对其前、中、后肠的细菌数量和组成进行了分析。结果发现 :与对照组相比 ,投喂喹乙醇的试验组鱼肠道菌群数均有不同程度的下降 ,其中 1 60 0、32 0 0mg/kg组的下降最为明显。从 1 60 0mg/kg开始前肠菌群数明显下降 ,在 40 0mg/kg时中肠菌群开始下降较为明显 ,后肠菌群数在各试验组均呈下降趋势。在对照组检出的 7种主要菌群也是构成各个实验组鱼肠道中的主要菌群 ,但这 7种菌群在各组中的组成比例不同 ,其中鲤鱼肠道菌属中Aer属、Aci属的组成比例变化较大 ,80 0mg/kg (1 1 0 6 % )、 1 60 0mg/kg (1 1 735% )和 32 0 0mg/kg (7 40 % )组中Aer所占比例明显低于对照组 (2 6 2 55 % ) ,而 80 0mg/kg (37 50 2 % )、 1 60 0mg/kg (36 52 % )和32 0 0mg/kg (41 357% )组中Aci所占比例明显高于对照组 (1 3 2 1 3% )。饲料中添加不同水平的喹乙醇可明显影响鲤鱼肠道主要菌群的数量及组成比例。

The influence of different concentrations of olaquindox (1,200,400,800,1600 and 3200mg/kg)in feed on microflora in the intestine of carp was investigated in a feeding trial lasting for 84d.Two fish sampled randomly from each group were used to determine the quantity and composition of their microflora in the fore,mid and hind gut at the end of this experiment.It was found that total intestinal microflora number of the fish treated with olaquindox generally decreased as compared with control.And the quantity of microflora in the intestine of carp fed with feed containing dosages of 1600 and 3200mg/kg decreased significantly.The microflora quantity in the fore gut when dosage of olaquindox rose to 1600mg/kg,that in the mid gut when the dosage of olaquindox rose to 400mg/kg,and that in the hind gut from the start of 200mg/kg began to decrease significantly,respectively.There were seven varieties of dominant microflora examined in the control,as were the same in olaquindox treated groups.But the composition of the microflora was not different among groups,in which Aer and Aci gave bigger changes.The percentage of Aer in corresponding total microflora of 11 06,11 74 and 7 41% at 800,1600 and 3200mg/kg were significantly lower that that in control.On the contrary,the 37 5,36 52 and 41 36% of Aci at 800,1600 and 3200mg/kg were all markedly higher than that in control.The results suggest that the quantity and composition of microflora in the intestine in carp would change when fish are fed with feed containing different dosages of olaquindox.