This experiment was conducted to study the influences of dietary maggot meal and L - carnitine on growth, non - specific immunity and antioxidant capacity of black carp (Mylopharyngodon piceus ). 270 healthy fish with initial body weight of (72. 23 ± 1. 81) g were selected and randomly divided into three groups;one control and two tested. Three isonitrogenous and isoenergetic diets were formulated, when the control group was fed with basal diet and two tested groups were fed with diets supplemented with 25 g/kg maggot meal and 150 mg/kg L - carnitine respectively. After feeding them for 60 days, we investigated the growth performance, muscle composition, biochemical parameters of blood and liver and mortality and relative survival rate after their infection with Aeromonas hydrophila. The results showed that, compared with the control, in maggot meal and L - carnitine groups, some indices were significantly improved such as the weight gain and specific growth rates, the levels of total protein ( TP) , lysozyme ( LSZ) , complement 3 and 4 (C3 and C4) ,glutathione peroxidase (GSH -Px) in serum and the activities of superoxide dis-mutase (SOD) ,CSH - Px and catalase ( CAT) in liver (P 0. 05). The other indices, such as serum glutamic - pyruvic transaminase (GPT) and glutamic - oxaloacetic transaminase (GOT),survival rates,the fish physical indices and muscle composition were not significantly different among the three groups (P >0. 05). The challenge experiment with A. Hydrophila showed that the mortality of fish could be reduced in the maggot meal and L - carnitine groups compared with the control. Therefore, the diet supplemented with 25 g/kg maggot meal or 150 mg/kg L - carnitine could promote the growth of black carp, improve the non - specific immunity and antioxidation capacity and enhance fish resistance to disease.%研究蝇蛆粉和L-肉碱对青鱼(Mylopharyngodon piceus)生长、非特异性免疫和抗氧化能力的影响.选取初始体重(72.23 ±1.81)g的健康青鱼270尾,随机分成3组,分别饲喂3种等氮等能的饲料,其中对照组投喂基础日粮,另外2组分别投喂添加25 g/kg蝇蛆粉或150 mg/kg L-肉碱的试验饲料.连续投喂60d后,测定鱼体生长指标、肌肉成分、血液和肝脏的生化指标,并统计青鱼感染嗜水气单胞菌(Aeromonas hydrophi1a)后的死亡率和相对保护率.结果表明,与对照组相比,蝇蛆粉和L-肉碱组显著提高鱼体增重率和特定生长率,血清总蛋白(TP)、溶菌酶(LSZ)、补体C3和C4、谷胱甘肽过氧化物酶(GSH-Px)的水平,以及肝脏超氧化物歧化酶(SOD)、GSH-Px和过氧化氢酶(CAT)的活性,降低饲料系数,血清和肝脏丙二醛(MDA)的含量(P＜0.05).此外,蝇蛆粉组还较对照组显著提高青鱼血清碱性磷酸酶(AKP)、SOD和CAT的活性(P＜0.05),而L-肉碱组的相应指标与对照组的差异不显著(P＞0.05)；其他一些指标如血清谷丙转氨酶(GPT)和谷草转氨酶(GOT)、成活率、鱼体形体指标以及肌肉组成成分等各组间差异均不显著(P＞0.05).攻毒试验也表明,蝇蛆粉和L-肉碱组均降低青鱼的死亡率.因此,在饲料中添加蝇蛆粉25 g/kg或L-肉碱150mg/kg可促进青鱼的生长,提高鱼体的免疫力和抗氧化能力,增强鱼体的抗病力.
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