试验旨在研究草鱼(Ctenopharyngodon idella)饵料中添加不同水平的杆菌七肽(Microcin C7)对其生长性能的影响,探讨杆菌七肽在草鱼养殖中的最适添加水平.研究选用400尾体重约15g的草鱼,按照单因素试验设计均分4个处理,每个处理4个重复,每个重复25尾草鱼.各组草鱼分别投喂含有0mg/kg、40mg/kg、80mg/kg和120mg/kg的杆菌七肽的试验饵料.预饲期1周,正式试验期8周.试验结束,检测各组草鱼的生长性能相关指标.结果表明,在草鱼养殖中添加80mg/kg和120mg/kg的杆菌七肽可以显著提高草鱼的试验末体重(P<0.05),分别比对照组显著提高了 19.12%、21.62%(P<0.05);显著提高了草鱼的增重率(P<0.05),分别比对照组显著提高了 29.23%、31.79%(P<0.05);特定生长率分别比对照组显著提高了 17.68%、22.10%(P<0.05);而添加80mg/kg和120mg/kg的杆菌七肽可以显著降低草鱼的饵料系数(P<0.05),分别比对照组显著降低了 8.87%、9.85%(P<0.05).研究表明,在草鱼养殖中使用适量的杆菌七肽可以显著改善草鱼的生长性能,综合养殖成本考虑,杆菌七肽的最适添加水平为80 mg/kg.
The experiment was designed to study the effects of adding different levels of Microcin C7 to the bait of grass carp(Ctenopharyngodon idella)on its growth performance,and to explore the optimum level of Microcin C7 to be added to the bait in grass carp culture.In the study,400 grass carp weighing about 15g were divided into 4 treatments with 4 replicates in each group and 25 fish in each replicate according to the one-way experimental de-sign.Each group was fed with test bait containing 0 mg/kg,40 mg/kg,80 mg/kg and 120 mg/kg of Bacillus hep-tapeptide.The pre-feeding period was 1 week and the formal test period was 8 weeks.At the end of the experi-ment,the growth performance related indexes of grass carp in each group were tested.The results showed that the addition of Microcin C7 at 80 mg/kg and 120 mg/kg in grass carp culture could significantly increase the weight of grass carp at the end of the test(P<0.05),which was significantly higher than that of the control group by 19.12%and 21.62%,respectively(P<0.05);and the weight gain rate of the grass carp was significantly higher than that of the control group by 29.23%,which was significantly higher than that of the control group by 29.23%,respectively(P<0.05),31.79%(P<0.05);specific growth rate was significantly increased by 17.68%and 22.10%(P<0.05),respectively,compared with the control group;and the addition of Microcin C7 at 80mg/kg and 120mg/kg significantly reduced the bait coefficient(P<0.05)of grass carp by 8.87%and 9.85%(P<0.05),respectively,compared with the control group.The study showed that the use of appropriate amount of Microcin C7 in grass carp culture can significantly improve the growth performance of grass carp,and the optimum level of Micro-cin C7 is 80 mg/kg considering the comprehensive culture cost.