不同促生长剂对虹鳟生长性能及非特异性免疫机能的影响

Effects of dietary growth promoter supplementation on growth performance and non-specific immunity function in rainbow trout Oncorhynchus mykiss

研究了不同促生长剂对虹鳟Oncorhynchus mykiss生长性能及非特异性免疫机能的影响。试验共设5个处理组:A、B组分别在饲料中添加那西肽2 mg/kg和4 mg/kg,C组添加大蒜素15 mg/kg,D组添加黄霉素8 mg/kg,E组为对照组。饲料为膨化饲料,粗蛋白的质量分数为43.05%,粗脂肪为23.02%。每个处理设3个重复,每个重复放80尾鱼,初始体重为(33.78±1.99)g。试验期间,水温为(14.5±2.0)℃,溶氧为(8.9±1.1)mg/L,每天饲喂2次。试验共进行56 d。结果表明:与对照组相比,A、C、D组虹鳟的特定生长率分别提高8.5%、6.9%和8.5%,饵料系数分别降低8.3%、7.5%和2.5%,增重率分别提高13.4%、10.35%和12.62%,鱼体粗蛋白分别提高2.69%、8.58%和2.88%,但差异均不显著(P>0.05);添加不同促生长剂,鱼体肾脏中SOD酶活性和肝脏中溶菌酶活性显著上升(P<0.05),肝脏和血浆中SOD酶活性及鳃组织中溶菌酶活性也有不同程度的提高。说明在饲料中添加2 mg/kg那西肽、15mg/kg大蒜素和8 mg/kg黄霉素,可以改善虹鳟的生长性能,提高鱼体的免疫活性。

An 8 week feeding trial was undertaken to evaluate the effects of dietary growth promoter supplementation including Nosiheptide（2 mg/kg, 4 mg/kg）, Allitridum（ 15 mg/kg） and Flavomycin （8 mg/kg） on growth performance and non- specific immunity in rainbow trout Oncorhynchus mykiss with initial average body weight of （ 33.78 ± 1.99） g at water temperature of （ 14.5 ± 2.0） ℃. Triplicate groups of 80 rainbow trout juveniles held under identical culture conditions （ disolved oxygen level of 8.9 ± 1. 1 mg/L） were fed twice daily to satiation one of five diets with equivalent protein （43.05%） and lipid （23.02%） content on a dry weight basis, but with supple mented with Nosiheptide at a rate of 2 mg/kg, and 4 mg/kg）, Allitridum at a rate of 15 mg/kg and Flavomycin at a rate of 8 mg/kg and without any growth promoter. The results showed that the juveniles fed the diet containing 2 mg/kg Nosiheptide, 15 mg/kg Allitridum and 8 mg/kg Flavomycin had 8.5% , 6.9% and 8.5% higher specific growth rate （SGR） than the fish in the control group, and 8.3%, 7.5% and 2.5% lower feed conversion ratio （FCR） than the fish in the control group. There were 13.4% , 10.35% and 12.62% higher weight gain rate （WGR） and 2.69% and 8.58% and 2.88% higher crude protein contents in the juveniles fed the diets containing 2 mg/kg Nosiheptide, 15 mg/kg Allitridum and 8 mg/kg Flavomycin than in the juveniles the control group, respectively. The activities of SOD significantly increased（ P 〈0.05 ） in kidney and the activities of lysozyme （LSZ） significantly increased（P 〈 0.05 ） in liver of the fish fed the diet supplemented with different levels of dietary growth promoters. The activities of SOD in liver and plasma and the activities of LSZ in gill were increased. It can be concluded that the growth performance and non - specific immunity of rainbow trout could be improved evidently by addition of 2 mg/kg nosiheptide and 15 mg/kg allitridum and 8 mg/kg Flavomyein.