微生态制剂对草鱼生产性能、肠道菌群及养殖水质的影响

Effects of microecological preparation on production performance,intestinal flora and water quality of grass carp

为研究微生态制剂(MicroecologicalPreparation,MP)对草鱼生产性能、肠道菌群及养殖水质的影响。试验将600尾初始体重相近,健康无病的草鱼随机分为4组,每组3个重复,每个重复50尾。其中,对照组(CON组)草鱼饲喂基础饵料,其余3组草鱼则在基础饵料中分别添加2g/kg(MP2组)、4g/kg(MP4组)、6g/kg(MP6组)的微生态制剂,试验为期60d。结果显示,(1)与CON组相比,MP2组、MP4组草鱼的终末体重、增重率、胴体重均显著提高(P <0.05)。(2)与CON组相比,MP6组肠道乳酸菌数量显著提高(P <0.05),大肠杆菌数量显著降低(P <0.05)。(3)与CON组相比,MP6组水体中40、60d氨氮浓度均显著降低(P <0.05),MP2组、MP4组、MP6组水体中20、40、60d亚硝酸盐浓度均显著降低(P <0.05),MP6组水体中20、40、60d硫化氢浓度显著降低(P <0.05)。结论:基础饵料中添加中低水平(2、4g/kg)的微生态制剂能促进草鱼生长;基础饵料中添加高水平(6g/kg)的微生态制剂能改善肠道菌群,优化养殖水质,降低水质中的有害物质。

To study the effects of microecological preparation(MP)on the production performance,intestinal flora and water quality of grass carp.600 healthy and disease-free grass carp with similar initial weight were selected for the experiment and randomly divided into 4 groups,with 3 replicates in each group and 50 replicates per replicate.Among them,the control group(CON group)grass carp were fed with basic diet,while the other three groups of grass carp were added with 2 g/kg(MP2 group),4 g/kg(MP4 group),and 6g/kg(MP6 group)of microecological preparation to the basic diet,respectively.The experiment lasted for a total of 60 days.The results showed that:(1)Compared with the CON group,the final body weight,weight gain rate,and carcass weight of grass carp in the MP2 and MP4 groups were significantly increased(P < 0.05).(2)Compared with the CON group,the number of lactic acid bacteria in the MP6 group was significantly increased(P < 0.05),while the number of Escherichia coli was significantly reduced(P < 0.05).(3)Compared with the CON group,the concentration of ammonia nitrogen in the water of the MP6 group significantly decreased after 40 days and 60 days(P < 0.05);the nitrite concentrations in the water bodies of the MP2,MP4,and MP6 groups were significantly reduced at 20d,40d,and 60d(P < 0.05);the concentration of hydrogen sulfide in the water of the MP6 group significantly decreased at 20d,40d,and 60d(P < 0.05).Conclusion:Adding medium and low level(2,4 g/kg)microecological preparation to the basic diet can promote the growth of grass carp;Adding high-level(6 g/kg)microecological preparation to basic bait can improve gut microbiota,optimize aquaculture water quality,and reduce harmful substances in water quality.