几株肠道益生菌对凡纳滨对虾非特异免疫力和抗病力的影响

以基础饲料为对照组,在基础饲料中分别添加坚强芽孢杆菌活菌(Bacillus firmus)、坚强芽孢杆菌活菌(1.0×108 CFU/g)+美人鱼发光杆菌(Photobacterium damsela)灭活菌(1％)、坚强芽孢杆菌活菌(1.0×108 CFU/g)+溶藻弧菌(Vibrio alginolyticus)灭活菌(1％)配制3种免疫饲料.每组3个重复,对个体质量为(3.2±0.26)g的凡纳滨对虾(Litopenaeus vannamei)进行了为期30d的养殖实验.每5d取样,以血清中的酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、一氧化氮合酶(NOS)、超氧化物歧化酶(SOD)和溶菌酶(UL)活性为免疫指标,探讨了肠道益生菌及其灭活菌体作为免疫制剂对凡纳滨对虾非特异性免疫水平的影响;在投喂免疫饲料后的第16天,按0.9 g/10尾剂量,直接投喂感染白斑综合征病毒(wssV)对虾病料,计算各实验组每天的累计死亡率,分析肠道益生菌及其灭活菌体作为免疫制剂对凡纳滨对虾病毒感染能力的影响.结果显示:添加益生菌的实验组对虾血清中SOD、ACP、AKP和NOS活性明显高于对照组(P＜0.05),特别是显著提高了对虾抗WSSV感染的能力.其中坚强芽孢杆菌活菌(1.0× 108 CFU/g)和美人鱼发光杆菌灭活菌(1％)实验组的抗病毒感染能力最强,感染WSSV 14 d后累计死亡率为10.71％;而对照组为64.28％.结论认为,饲料中添加肠道益生菌及其灭活菌体能提高凡纳滨对虾非特异性免疫水平和抵抗疾病的能力,有望作为新型对虾免疫增强剂应用于对虾养殖业.

Effects of probiotics from the shrimp intestine on the non-specific immunity and antiviral capacity of Litopenaeus vannamei

We evaluated the effects of probiotics on the non-specific immunity and antiviral capacity of Litopenaeus vannamei. We fed groups of shrimp (body weight 3.2 g±0.26 g) a diet supplemented with either 1.0×10⁸ CFU/g Bacillus firmus (live) plus 1% Photobacterium damsela (inactivated), 1.0×10⁸ CFU/g Bacillus firmus (live), or 1.0×10⁸ CFU/g Bacillus firmus (live) plus 1% Vibrio alginolyticus (inactivated). The control groups were fed a non-supplemented diet. Each diet was fed to triplicate groups of 60 shrimp that were reared in aquaria. We randomly selected 10 shrimp per group every 5 d and measured a range of humoral immune parameters (superoxide dismutase SOD, acidic phosphatase ACP, alkaline phosphatase AKP, nitric oxide synthase NOS and lysozyme UL) in each individual. The shrimp were challenged with white spot syndrome virus (WSSV) after two weeks. We then calculated the cumulative mortality of each experimental group. Supplementation with bacteria significantly increased serum SOD, ACP, AKP, and NOS compared with the controls. There was significantly lower cumulative mortality in shrimp that were fed the probiotics diet (10.7%, 39.3% and 26.2%, respectively) compared to the control (64.28%). Our results suggest that supplementing the diet with shrimp intestine probiotics improves immunity and the antiviral capacity of Litopenaeus vannamei.