锌铜铁对水产动物免疫机能的影响

矿物元素作为五大营养素之一不仅可满足水产动物的营养需求,还可加强其特异性和非特异性免疫反应。本文综述了水产动物的免疫系统及免疫相关的酶等因子,以及饲料和水体中的矿物元素锌、铜和铁对水产动物免疫机能的影响。     

Dietary vitamin C,immunity and disease resistance in Atlantic salmon (Salmo salar)

Presmolt Atlantic salmon were fed a fish meal based experimental diet supplemented with graded levels of ascorbate-2-monophosphate (AP), equivalent to 40, 400, 2000 and 4000 mg ascorbic acid (AA)/kg for 6 months prior to a bacterial challenge experiment. The liver AA concentration reflected the dietary intake of AP, but not linearly. Growth, hematology and acid phosphatase activity in zymosan stimulated macrophages were not affected by dietary AP. Serum hemolytic complement activity was higher in fish fed the highest AP level, but the variation was not significant. Production of specific antibodies was significantly higher in fish fed the highest AP level 11 and 17 weeks after vaccination. Bacterial challenge with Aeromonas salmonicida showed increased survival in the 4000 AP group. Lysozyme activity in headkidney and serum complement activity and serum iron in fish surviving the challenge were higher in the 4000 AP group, indicating important roles of vitamin C on lysozyme, complement and iron in non-specific disease resistance. The results indicate that high dietary levels of AP favourably affect health in Atlantic salmon. Disease resistance was, however, not correlated with the AA status in the liver.     

The eel immune system: present knowledge and the need for research

The European eel, Anguilla anguilla, is one of the most important warm water fish species cultured in southern Europe and the Mediterranean as well as in northern countries including Germany, the Netherlands and Denmark. The Japanese eel, A. japonica, is an important cultured fish in several Asiatic countries including Japan, China and Taiwan. During recent decades, research has been performed to elucidate the immune response of these species against different pathogens (viruses, bacteria or parasites). Nevertheless, there is very limited information in terms of both cellular and humoral immune responses. This review summarizes the present knowledge relating to the eel immune system and includes new data.     

养殖密度对日本黄姑鱼幼鱼生长及非特异性免疫的影响

以初始体质量(7.67±0.85)g的日本黄姑鱼(Nibea japonica)为实验对象,研究了不同养殖密度对日本黄姑鱼幼鱼生长和非特异性免疫的影响:将其随机分为5组,每缸(200 L)分别放养50、100、150、200、250ind幼鱼,密度分别相当于1.9、3.8、5.7、7.6、9.0 kg·m-3,依次记为G1、G2、G3、G4、G5,养殖时间为30 d。结果显示,G5组幼鱼增重率显著低于其它各组(P0.05),其成活率也较低。血清溶菌酶活性、皮质醇含量随着养殖密度的增加分别表现出降低、增加的趋势,但各组间差异不显著。不同养殖密度下日本黄姑鱼幼鱼的肾脏、肝脏、肌肉及鳃中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、碱性磷酸酶(AKP)和酸性磷酸酶(ACP)活力有所不同,但总体上没有明显差异。结果表明,本实验条件下,不同实验密度组间日本黄姑鱼幼鱼生长及存活出现了差异,但其非特异性免疫性能并未受到明显影响。     

美人鱼发光杆菌对凡纳滨对虾非特异性 免疫功能及抗病力的影响

在基础饲料中分别添加0.1%和1%美人鱼发光杆菌灭活菌、0.1%美人鱼发光杆菌活菌配制成3种免疫实验饲料,以基础饲料为空白对照组饲料,每组设3个平行样。对个体质量为(4.83±0.36)g的凡纳滨对虾进行为期20 d的饲养实验,分别在0、5、10、15和20d进行取样,以血清中的酚氧化酶(PO)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、超氧化物歧化酶(SOD)和溶菌酶(UL)活性为免疫指标,探讨了美人鱼发光杆菌作为免疫制剂对凡纳滨对虾非特异性免疫效应的影响;在投喂免疫饲料后的第22天,按0.004 2 kg/kg体重的剂量,直接投喂对虾白斑综合征病毒(WSSV)病料,并记录累积死亡率。结果表明,美人鱼发光杆菌免疫实验组对凡纳滨对虾血清中PO、ACP、AKP、UL和SOD活性影响明显高于对照组,并且在饲料中添加美人鱼发光杆菌后,明显提高了对虾抵御WSSV感染的能力。其中0.1%美人鱼发光杆菌活菌实验组的抗病毒感染能力最强,WSSV感染14d内累计死亡率为63.3%±5.8%;而对照组为96.7%±3.3%。研究表明,美人鱼发光杆菌添加在对虾饲料中能提高凡纳滨对虾非特异性免疫水平,增强抵抗疾病的能力,将其作为对虾免疫增强剂具有良好的应用前景。     

饲料中添加龙须菜对眼斑拟石首鱼生长、脂肪酸组成、免疫及肠道的影响

为了研究添加龙须菜(Gracilaria lemaneiformis)对眼斑拟石首鱼(Sciaenops ocellatus)生长、脂肪酸组成、免疫和肠道的影响,在饲料中分别添加0(对照组)、1%、2%、3%、4%和5%的龙须菜,饲养初始体质量(9.38±0.06)g的眼斑拟石首鱼8周。结果表明,添加龙须菜对鱼体成活率、增重率(WG)和特定生长率(SGR)均不存在显著性影响(P0.05),但1%~4%组的增重率均高于对照组,1%组的饲料效率和特定生长率最高;所有龙须菜添加组全鱼脂肪酸中的二十二碳六烯酸(DHA)均高于对照组,且添加量为5%时DHA显著高于对照组(P0.05);肝脏中超氧化物歧化酶(SOD)活性在4%组显著高于对照组(P0.05);3%组肠道黏膜褶最高且组织状况最好。由此可见,饲料中添加龙须菜对眼斑拟石首鱼生长有一定的促进作用,且添加适量龙须菜可以改善眼斑拟石首鱼的肝脏和肠道健康,提高全鱼DHA含量。     

Effect of Lactococcus lactis and Enterococcus faecium on growth performance,digestive enzymes and immune response of grouper Epinephelus coioides

The effect of dietary administration of Lactococcus lactis MM1 and Enterococcus faecium MM4, two strains of lactic acid bacteria isolated from the gut of juvenile grouper Epinephelus coioides, on the growth, feed utilization, digestive enzymes and immune response of juvenile E. coioides was evaluated. The fish were fed for 60 days with three different diets: control diet (without probiotic), diet P1 supplemented with 1.0 × 10⁸ CFU g^?1L. lactis or diet P2 with 1.0 × 10⁸ CFU g^?1E. faecium. Although growth and feed intake decreased slightly, significant improvement of feed utilization was observed in fish fed diet P1 and diet P2 for 60 days. The hepatopancreatic protease activities in the two probiotic treatments were significantly higher than that in the control. The phagocytic activity, serum superoxide dismutase activity and complement component 4 (C4) and IgM levels were not significantly affected by diet P1 and diet P2. Serum complement component 3 (C3) levels in the two treatments were significantly higher than that in the control. Significant increased serum lysozyme activity was observed in fish fed the diet P1, while significant decreased lysozyme activity was observed in fish fed the diet P2 compared with the fish fed the control diet. There was a significant interaction effect between diet and administration date for the complement C4. The study demonstrates potential for L. lactis MM1 and E. faecium MM4 to improve the feed utilization and modulate the immune function in E. coioides.     

养殖密度对温室湿地循环水系统中鲫生长、生理及免疫指标的影响

研究了基于两级人工湿地的温室循环水系统中,养殖密度对鲫（Carassius cuvieri）生长、脏器系数、血清生理免疫指标及对嗜水气单胞菌（Aeromonas hydrophila）抵抗力的影响。试验设2 kg·m^-3、4 kg·m^-3、8 kg·m^-3和16kg·m^-3共4种密度组,每组2个平行,养殖68 d。结果显示：1）各养殖密度下鲫生长及脏器系数不存在显著差异;2）与2 kg·m^-3组鲫相比,16 kg·m^-3组鲫血清丙二醛（MDA）质量摩尔浓度显著升高,溶菌酶（LSZ）、酸性磷酸酶（ACP）和碱性磷酸酶（AKP）活性显著降低,超氧化物歧化酶（SOD）活性和总蛋白质量浓度虽有不同程度升高,但差异不显著;3）高密度组鲫对嗜水气单胞菌的抵抗力较低密度组弱。以上结果表明,如果以生长为考量指标,温室湿地循环水系统中鲫养殖密度可达16 kg·m^-3,但如此高的密度会对鲫免疫力造成负面影响。     

果寡糖对急性氨氮应激下团头鲂非特异性免疫指标的影响

为研究氨氮应激条件下果寡糖对团头鲂(Megalobrama amblycephala)非特异免疫指标的影响,试验选择360尾初重为13.5 g的团头鲂随机分为3组,每组4个重复,每缸30尾鱼,对照组投喂基础日粮,试验组分别投喂果寡糖(FOS)添加量为0.4%和0.8%的日粮,饲养8周,养殖试验结束后,用10 mg/L的NH4Cl对24尾鱼进行氨氮应激试验。试验结果显示,氨氮应激前,0.4%FOS组的血液谷丙转氨酶(GPT)活性显著低于对照组和0.8%FOS组,在氨氮应激后,0.4%FOS组的GOT活性有降低的趋势,但仅在24 h时显著低于0.8%组,0.8%组和对照组之间并无显著差异;血清酸性磷酸酶、补体3(C3)、补体4(C4)、酚氧化酶都出现先升高后降低的趋势,分别在应激后的3、24、12、12 h达到最大值。此外,应激前0.4%FOS组补体C3、C4、酚氧化酶的活性都显著高于对照组,应激后0.4%FOS组C3在3 h处显著高于对照组,但是在其它时间点各组差异并不显著,果寡糖添加水平和采样时间对这些免疫指标都无显著的交互作用。结果表明饲料中添加0.4%的果寡糖能够提高团头鲂的免疫力指标活性,提高了团头鲂抗氨氮应激的能力。     

Effects of dietary xylooligosaccharides on growth performance,immunity and Vibrio alginolyticus resistance of juvenile Litopenaeus vannamei

A 60‐day feeding trial was conducted to assess the effects of xylooligosaccharides on growth performance, immunity and Vibriosis alginolyticus resistance of juvenile Litopenaeus vannamei. Five diets were formulated to contain 0 (T0), 1 (T1), 2 (T2), 4 (T4) and 6 (T6) g/kg of xylooligosaccharides, triplicate groups of 40 shrimps with initial weight of 0.10 ± 0.01 g were fed to apparent satiation four times daily. At the end of the feeding trail, ten shrimps from each tank were challenged with V. alginolyticus. Results showed that shrimps fed xylooligosaccharides containing diets had higher (p < 0.05) feed efficiency, survival rate and intestinal villi length and area than those of T0. There was no significant difference in final body weight, weight gain rate and chemical compositions of whole shrimp among treatments. Shrimps fed T4 and T6 diets had higher (p < 0.05) phenoloxidase and lysozyme activities than those in T0. Concentration of albumin, phenoloxidase activity and survival rate of shrimps decreased (p < 0.05) after 72 hr of challenge, with SR being greater (p < 0.05) in T2, T4 and T6 than that of in T0. Results demonstrate that supplementing 4–6 g/kg of xylooligosaccharides in diets increased feed efficiency, survival rate, intestinal villi length and area, and improved the resistance of juvenile L. vannamei against V. alginolyticus. This study suggests that xylooligosaccharides could be a potential feed additive in practical diet of juvenile L. vannamei.