感染嗜水气单胞菌鱼类组织病理变化与多组学分析的研究进展

嗜水气单胞菌感染引起的病害使我国鱼类养殖遭受了严重经济损失，制约了水产养殖业的健康发展。嗜水气单胞菌可产生多种毒力因子，致病过程及影响因素复杂，感染鱼类种类广。鱼类的肠道、脾脏、肝脏和肾脏具有重要的免疫功能，在抵御病原菌入侵中发挥重要作用，其中肠道菌群直接影响着宿主的免疫和炎症反应。本文着重阐述了嗜水气单胞菌感染后鱼类免疫相关器官的组织病理学变化、转录组水平基因的差异表达和通路富集及肠道微生物组成与结构改变，综述了嗜水气单胞菌感染后鱼类病理学和组学水平变化，为研究鱼类免疫应答机制及肠道菌群免疫调节功能提供参考依据。     

鱼类肠道微生物研究进展

肠道微生物种类和含量丰富,对机体生长发育具有重要影响。鱼类作为脊椎动物的重要组成部分,其生活在水体环境中,肠道微生物容易受到食物、压力、宿主生长发育、环境等影响,同时对机体的营养、生长、和免疫等都有重要作用。本文综述近年来国内外对鱼类肠道微生物的研究进展,阐述鱼类肠道菌群的影响因素、肠道微生物对机体营养代谢、免疫调节等的影响,以期为鱼类等水生动物的生态健康养殖提供理论支撑,推动水产养殖业的可持续发展。     

鱼类黏膜层微生物研究进展

鱼类黏膜层(主要为皮肤、鳃、肠道等部位)及其共生微生物在调节鱼类黏膜层微环境稳态、促进鱼体健康方面发挥重要作用。近10年来,鱼类肠道黏膜层微生物因其在鱼体营养和健康方面具有重要作用而备受关注,而人们对于其他部位黏膜层(如皮肤、鳃)共生微生物的研究却相对滞后。为更好地了解鱼类黏膜层微生物与鱼体健康的关系,本文将结合近年来的研究结果,对鱼类黏膜层微生物的群落特征、与宿主的相互作用、影响因素、研究策略和应用价值等方面对鱼类黏膜层微生物的研究现状和存在问题进行综述,旨在为鱼类黏膜层微生物未来研究的发展方向,及其在生产、实践方面的应用提供理论参考。     

鱼类肠道菌群影响因子研究进展

肠道菌群在维持肠道健康、促进肠道发育、抵抗病原入侵、调节机体能量吸收和脂质代谢过程中均发挥重要作用。在鱼类学研究中,由于种类繁多、食性差异大、生存环境复杂多变,导致鱼类肠道菌群方面的研究面临巨大挑战。本文在总结常见鱼类肠道微生物组成的基础上,着重介绍了鱼类饵料组成、水环境因子、物种、基因型、发育阶段、养殖模式及投喂策略对鱼类肠道菌群影响的相关研究进展,并对目前研究中存在的问题进行了剖析,以期为鱼类肠道菌群研究提供一定的参考依据。     

投喂板蓝根、大黄对草鱼肠内细菌的影响

草鱼是我国普遍养殖的一种重要经济鱼类，天然状态下主要以高等水生植物为食，又可经驯化摄食人工配合饲料。但因其对多种病原菌易感，尤其是在自身抵抗力（免疫力）下降时，可给养殖生产造成巨大的经济损失。在生产实践中，中草药板蓝根、大黄常用来防治细菌性疾病，但其作用的机理还未清楚。有关报道认为，肠道细菌的存在对鱼类健康具有重大意义犤１～５犦。为此，观测草鱼摄食含中草药饲料后肠道菌群的演替，并结合肠道菌群的组成和数量范围的变化，了解肠道菌群和中草药之间的关系，以找到合适的中草药，为实际生产中新型保健鱼药的开发…     

鱼类肠道正常菌群研究进展

鱼类肠道正常菌群是肠道的正常组成部分;是肠道微生物与宿主以及所处的水生环境形成的相互依赖、相互制约的微生态系;对营养物质的消化吸收、免疫反应以及器官的发育等方面具有其他因素不可替代的作用,并且影响到鱼类的生长、发育、生理和病理。笔者拟就鱼类肠道菌群的形成、结     

鱼类健康与肠道微生物关系研究进展

鱼类肠道内有着种类丰富、数量庞大的微生物,本文阐述了鱼类肠道微生物对机体的营养消化吸收、机体免疫力及抵制疾病等方面的重要作用,及肠道微生物本身受环境、饵料、鱼体自身生长发育等因素的影响。     

水产动物肠道健康保健新措施

正水产动物肠道不仅是重要的消化和吸收器官,同时还具有免疫、内分泌以及新陈代谢的功能。肠道病变往往会引起机体其他器官(如肝胰脏)的损伤和功能障碍,因此维护肠道健康是水产养殖生产的核心,更是养殖成功的关键一环。本文简述了几种维护肠道健康的保健措施,尤其是葡萄糖氧化酶、溶菌酶、肠道损伤修复剂等新产品的应用。一、影响水产动物肠道健康的因素1.饲料对肠道健康的影响饲料中含有一些对鱼、虾、蟹有害的物质,如饲料中的油脂氧化物、霉菌毒素、     

鱼类的营养与健康、疾病的关系

鱼类的营养需要一方面提供生长发育所需的营养物质,另一方面则提供为维持机体健康所需的营养物质。营养状况是决定鱼类抗病能力的重要因素之一,各种影响因素的变化包括营养状况变差都会引起鱼类应激反应,引发疾病。因此,营养物质供给不平衡或缺乏,机体自然生长受阻,影响健康,严重的导致疾病的发生。营养与健康、疾病有着直接的密切关系。     

抗菌肽与鱼类肠道健康研究进展

我国是水产养殖大国,随着高密度、集约化养殖模式的发展,养殖中各种病害频繁发生,大量甚至提前使用抗生素进行病害预防相当普遍,抗生素的残留及耐药性对我国水产养殖业造成了严重影响。在纷纷寻求抗生素替代物的背景下,抗菌肽具有广谱抗菌性,较抗生素而言具有独特的抗菌机理,养殖过程中使用抗菌肽不易产生耐药性菌株,又具有提高鱼类等水生动物的生产性能及非特异性免疫功能等作用,正逐渐成为替代抗生素的新型抗菌药物而用于水产养殖中。目前有关抗菌肽在水产养殖上的应用研究主要集中在鱼类等水生动物自身产生的抗菌肽以及作为饲料添加剂的外源性抗菌肽。外源抗菌肽经摄食途径进入肠道,改善鱼类肠道的肠绒毛、肠皱襞高度及肌层厚层等组织形态结构,促进消化吸收功能;调节肠道菌群结构,在杀灭肠道有害微生物的同时增加益生菌含量,改善肠道微环境;在提高肠道消化酶活性和抗氧化能力等方面保障鱼类的肠道健康,同时提高鱼类生产性能、改善其品质、增强鱼体抗氧化和免疫功能[1-3]。笔者着重从水产养殖中抗菌肽饲料添加剂的来源及其与肠道菌群、肠道组织结构、肠道消化功能等相关研究进行总结分析,探讨存在的问题和对策,为抗菌肽在水产养殖中的应用,特别是保护鱼类肠道健康提供参考。     

应用高通量测序技术分析大菱鲆幼鱼肠道及其养殖环境的微生物群落结构

采用基于Illumina测序平台的高通量测序技术,对大菱鲆(Scophthalmus maximus)幼鱼肠道及其养殖水体、生物饵料中细菌种类及丰度进行研究。测序结果显示,养殖水体、生物饵料和大菱鲆幼鱼肠道等19个样品共获得有效序列547621条,可聚类于3771个可分类操作单元(OTUs),归属于养殖水体、生物饵料、健康幼鱼和发病幼鱼的操作分类单元(OTU)个数分别为3038、1090、87和777,其中,健康幼鱼与生物饵料、健康幼鱼与养殖水体特有的OTU个数分别为57和0,发病幼鱼与生物饵料、发病幼鱼与养殖水体特有的OTU个数分别为481和31。表明幼鱼肠道微生物多样性与生物饵料密切相关。根据细菌注释结果,拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria)在大菱鲆幼鱼肠道中占优势地位,其中,健康幼鱼肠道微生物共聚类为8个门,发病幼鱼的肠道微生物可聚类为19个门。与健康幼鱼相比,发病幼鱼肠道门水平上的3种主要优势菌群落结构出现失衡。此外,对各样品中丰度最高的100位OTU分析显示,幼鱼肠道优势菌种类与生物饵料中的优势菌种类密切相关,而每个发病幼鱼肠道优势菌种类具有一定的独立性。本研究旨在为大菱鲆健康养殖和微生态调控提供实验依据。     

Effect of dietary glutathione supplementation on the biological value of rapeseed meal to juvenile grass carp,Ctenopharyngodon idellus

An 8‐week feeding trial was conducted to investigate the effects of dietary rapeseed meal (RM) and glutathione supplementation (400 mg kg^?1) on growth and intestinal microbiota of grass carp (Ctenopharyngodon idellus). Dietary 450 g kg^?1 RM decreased growth and feed intake, while increased the activities of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine transaminase (ALT). The hepatic damages were also observed the significant lower condition factor (CF), hepatosomatic index (HSI) and the symbol of parenchymal damage. Glutathione supplementation increased weight gain and feed intake while significantly decreased the three serum biochemistry parameters compared with the RM group. In addition, HSI, CF and pathology reports revealed that glutathione supplementation alleviated the damage caused by RM on the fish liver. In addition, glutathione had a positive effect on the intestinal digestive capacity. PCR‐denaturing gradient gel electrophoresis (DGGE) analysis indicated a higher similarity between dietary glutathione supplementation and control group. In conclusion, we demonstrated dietary 450 g kg^?1 rapeseed meal lead to negative health outcomes, while glutathione supplementation neutralize the adverse effect of rapeseed meal presented in aqua feed through alleviating the damage factors on the fish liver.     

Heat Shock Protein Regulation in Rainbow Trout,Oncorhynchus mykiss,is Altered by Dietary Soybean Meal Inclusion and Anti‐Phopholipase A2 Antibody

Heat shock proteins (Hsps) can promote integrity of damaged intestinal epithelial tissues. The aim of this study was to determine the effects of a commercially available anti‐phospholipase A₂ antibody on growth, feed efficiency, Hsp expression, and intestinal health of rainbow trout fed diets containing high levels of soybean meal (SBM). Six practical‐type diets (45% protein; 15% fat) were formulated to contain 0, 17.5, or 35% SBM with and without antibody. Each diet was fed to three replicate tanks of fish (20 fish/tank; initial weight 21 g) for 9 wk. RNA was isolated from liver and intestinal tissues (n = 3/tank) to detect alterations in Hsp 27, Hsp 70, and Hsp 90 expression. Fish fed a diet containing 35% SBM had decreased growth and intestinal damage. Hsp 27 and Hsp 90 mRNA was elevated in fish fed 35% SBM. Fish fed 35% SBM with antibody had lower Hsp 90 mRNA expression than fish without antibody. These data indicate that feeding rainbow trout high levels of SBM alters the expression of some Hsps and anti‐phospholipase A₂ antibody supplementation does not normalize growth or prevent distal enteritis in fish fed 35% SBM.     

Dynamic distribution of intestinal microbes in Schizothorax o’connori at different growth stages

Fisheries Science - Gut microbes are closely related to physical health. The intestinal microbial population in fish is a complicated ecological environment that plays an important role in the...     

两种疾病发生对养殖半滑舌鳎肠道菌群结构的影响分析

为研究疾病发生情况下鱼类肠道菌群的结构变化,运用高通量测序方法分别对感染腹水病和皮肤溃疡病的工厂化养殖半滑舌鳎病鱼及同一养殖系统中健康鱼的肠道菌群结构进行了对比分析。结果发现,养殖半滑舌鳎肠道中的细菌种类要明显少于环境中的细菌种类,仅为养殖池进水和颗粒饲料中细菌种类总数的14.3%~44.7%。在疾病发生后,病鱼肠道中的细菌种类数量仅是同一养殖系统中健康鱼肠道细菌种类数量的45.8%和64.5%,病鱼肠道中细菌多样性下降非常明显。进一步分析肠道菌群结构的组成发现,虽然发病鱼和健康鱼肠道中超过60%的细菌种类不相同,但优势菌群的结构组成差异不明显,丰度最高的前10种细菌种类基本相同,其比例超过肠道相对总菌量的80%。不同疾病的发生对半滑舌鳎肠道菌群结构的影响也不同,腹水病会造成肠道中优势菌株的种类和相对丰度都发生比较明显的改变,而皮肤溃疡病发生前后肠道菌群结构组成几乎没有变化。研究表明,养殖半滑舌鳎的肠道菌群结构相对比较保守,而且并不是所有的疾病种类都会引起肠道菌群结构发生改变。     

Effects of rearing temperature and dietary short‐chain fructooligosaccharides supplementation on allochthonous gut microbiota,digestive enzymes activities and intestine health of turbot (Scophthalmus maximus L.) juveniles

The gut microbiomes of fish play important roles in host development, digestion and health. Evidence suggests that abiotic factors, such as diet and rearing temperature, could affect fish gut microbiota. In this study, the effect of dietary short‐chain fructooligosaccharides (scFOS) on turbot intestinal health, microbiota and digestive enzymes was investigated at two rearing temperatures: 15 and 20 °C. Four practical diets were supplemented with scFOS at 0, 5, 10 and 20 g kg^?1. scFOS did not affect fish performance. PCR‐DGGE did not show differences in bacterial profiles between dietary treatments; however, the number of operational taxonomic units, richness and diversity were higher at 20 °C. Enzyme activities in the foregut were not affected by rearing temperature, while in the hindgut, enzyme activities were higher at 15 °C. Total alkaline protease, α‐amylase and lipase activities in the foregut were higher in fish fed 20 g kg^?1 scFOS. Prebiotic supplementation had no effect on hindgut α‐amylase activity, while lipase activity of fish reared at 20 °C was higher in fish fed diet with 5 g kg^?1 scFOS. No differences were observed in intestinal morphology. This was the first study to simultaneously evaluate the effect of dietary prebiotic level and rearing temperature on fish intestinal microbiota and health.     

An outbreak of botulism in rainbow trout, Salmo gairdneri Richardson, farmed in Britain

Abstract. An outbreak of disease in a British trout farm was identified as fish botulism. The diagnosis was established by demonstration of toxin in the serum and intestinal contents of fish, and was confirmed by the production of experimental botulism in trout inoculated with toxin from a strain of Clostridium botulinum type E isolated from intestinal contents of a sick fish. The outbreak was controlled and eliminated within 1 month by conservative measures which comprised the emptying, cleaning and heavy liming of affected ponds; intensive examination of all ponds for immediate removal of dead and sick fish and, on public health grounds, the banning of movement of fish outwith the farm. This episode, although of considerable financial consequence to the farmer, was shown to have no public health significance.     

Probiotics in fish and shellfish culture: immunomodulatory and ecophysiological responses

Aquaculture is emerging as one of the most viable and promising enterprises for keeping pace with the surging need for animal protein, providing nutritional and food security to humans, particularly those residing in regions where livestock is relatively scarce. With every step toward intensification of aquaculture practices, there is an increase in the stress level in the animal as well as the environment. Hence, disease outbreak is being increasingly recognized as one of the most important constraints to aquaculture production in many countries, including India. Conventionally, the disease control in aquaculture has relied on the use of chemical compounds and antibiotics. The development of non-antibiotic and environmentally friendly agents is one of the key factors for health management in aquaculture. Consequently, with the emerging need for environmentally friendly aquaculture, the use of alternatives to antibiotic growth promoters in fish nutrition is now widely accepted. In recent years, probiotics have taken center stage and are being used as an unconventional approach that has numerous beneficial effects in fish and shellfish culture: improved activity of gastrointestinal microbiota and enhanced immune status, disease resistance, survival, feed utilization and growth performance. As natural products, probiotics have much potential to increase the efficiency and sustainability of aquaculture production. Therefore, comprehensive research to fully characterize the intestinal microbiota of prominent fish species, mechanisms of action of probiotics and their effects on the intestinal ecosystem, immunity, fish health and performance is reasonable. This review highlights the classifications and applications of probiotics in aquaculture. The review also summarizes the advancement and research highlights of the probiotic status and mode of action, which are of great significance from an ecofriendly, sustainable, intensive aquaculture point of view.     

四种不同食性鱼类肠道微生物群落组成及多样性比较分析

本研究旨在探讨食性对鱼类肠道菌群组成和多样性的影响,并预测特定菌群对不同营养素的潜在功能。实验采用高通量16S rRNA基因测序技术,提取获得滇池高背鲫(Carassius auratus)、草鱼(Ctenopharyngodon idellus)、鳜鱼(Siniperca chuatsi)、昆明裂腹鱼(Shizothorax grahami) 4种不同食性鱼类的肠道内容物,12个样品的16S rRNA,构建文库并测序,分析这4种鱼类肠道微生物的菌落组成和多样性。结果显示,鱼类肠道菌群多样性受到食性的显著影响(P<0.05),综合表现为杂食性(滇池高倍鲫) > 草食性(草鱼) > 滤食性(昆明裂腹鱼) > 肉食性(鳜鱼)。4种鱼类具有一些相同的优势菌群：变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)。然而,优势菌群在属水平上存在一定差异,如不动杆菌属(Acinetobacter)为鳜鱼的优势菌群,拟杆菌属(Bacteroides)为草鱼的优势菌群等。功能预测发现,鳜鱼肠道中以革兰氏阴性菌为主;草鱼抗病潜力略高于其他3种鱼类;约氏不动杆菌(A._ johnsonii)、鲁氏不动杆菌(A. lwoffii)和施氏假单胞菌(Pseudomonas stutzeri)可能有助于宿主对蛋白质的消化,而拟杆菌属中的某些菌群可能有助于宿主消化纤维素。综上所述,食性是影响鱼类肠道菌群组成和多样性差异化的主要因素之一,分析食性与肠道优势菌群之间的关联,探讨特异菌群的功能,可为研究鱼类营养代谢的微生物效应奠定理论基础。     

Association of health involvement and attitudes towards eating fish on farmed and wild fish consumption in Belgium,Norway and Spain

Consumers in many European countries do not equally meet the recommended daily intake levels for fish consumption. Various factors that can influence fish consumption behaviour have been identified but limited research has been performed on fish consumption behaviour, discriminating between farmed and wild fish. The present survey study confirmed differences in total fish consumption, farmed fish and wild fish consumption behaviour in Belgium, Norway and Spain. Spanish consumers consumed more frequently fish of each category than Norwegian consumers. Belgian consumers reported the lowest consumption frequency of fish. Accordingly, health involvement and attitudes towards fish consumption decreased from Spain over Norway to Belgium, suggesting a positive association of health involvement and attitudes towards fish consumption with total fish consumption. Similar effects were found for farmed and wild fish consumption. In general, consumers in all countries were poorly aware of the origin of the fish they consume, despite the mandatory indication of origin on fish labels. Across countries, an increased awareness about fish origin was found with increased fish consumption. The findings of the study indicate that farmed and wild fish consumption should be further stimulated among Belgian, Norwegian and Spanish consumers in association with a healthy and positive meal. Additionally, given the limited awareness of the origin of fish, transparency on the issue of farmed origin will be important in order to anticipate potential adverse communication.