黄河源园区水生态功能一二级分区

生态功能分区是区域水生态系统区划及水环境规划管理的基础,也是生态文明建设背景下更为全面和系统性的分析和规划。出于三江源国家公园区域生态保护与分区管理,为探究地表水资源及生态系统的空间格局分异规律,以黄河源园区为研究对象,在综合分析其自然环境条件和水陆生态控制因子的基础上,结合园区内部各区域生态地理特征,基于GIS和RS平台,构建黄河源园区水生态功能分区评价指标体系。通过空间自相关距离确定降水、河网密度和地貌3个一级分区指标以及植被指数、植被生产力、土壤类型、土地利用类型4个二级分区指标;基于子流域完整性,运用数据叠加技术将黄河源园区分为5个一级水生态功能分区和19个二级水生态功能分区,运用相关性分析检验分区的合理性和准确性,并讨论了不同区域的生态系统特征和主要生态环境问题,阐述了水资源、植被资源的空间特征和分布规律。分区结果可为区域水陆环境的管理和保护利用提供科学依据与目标定位。     

Incidence of Pathogenic Microorganisms in Aquacultured Rainbow Trout (Oncorhynchus mykiss)

ABSTRACT

Quantitative levels of six known pathogens (Listeria monocytogenes, Clostridium botulinum, Salmonella species, Vibrio cholerae, Yersinia enterocolitica, and Y. pseudotuberculosis) and aerobic plate counts were measured at five aquaculture facilities. The farmed rainbow trout (Oncorhynchus mykiss) and trout fillets were sampled at two different growing seasons to monitor for microbial hazards. Listeria spp. was identified in both whole trout and trout fillets from all five facilities sampled from both growing seasons. Presumptive Clostridium botulinum spores were also identified from all five facilities for both seasons. The growing season did not affect pathogen levels and there was no evidence that any one aquacultural system was superior to the others. Salmonella spp., Vibrio cholerae, and Yersinia spp. were not isolated from any of the trout samples analyzed.     

Effect of dietary components on the gut microbiota of aquatic animals. A never‐ending story?

It is well known that healthy gut microbiota is essential to promote host health and well‐being. The intestinal microbiota of endothermic animals as well as fish are classified as autochthonous or indigenous, when they are able to colonize the host's epithelial surface or are associated with the microvilli, or as allochthonous or transient (associated with digesta or are present in the lumen). Furthermore, the gut microbiota of aquatic animals is more fluidic than that of terrestrial vertebrates and is highly sensitive to dietary changes. In fish, it is demonstrated that [a] dietary form (live feeds or pelleted diets), [b] dietary lipid (lipid levels, lipid sources and polyunsaturated fatty acids), [c] protein sources (soybean meal, krill meal and other meal products), [d] functional glycomic ingredients (chitin and cellulose), [e] nutraceuticals (probiotics, prebiotics, synbiotics and immunostimulants), [f] antibiotics, [g] dietary iron and [h] chromic oxide affect the gut microbiota. Furthermore, some information is available on bacterial colonization of the gut enterocyte surface as a result of dietary manipulation which indicates that changes in indigenous microbial populations may have repercussion on secondary host–microbe interactions. The effect of dietary components on the gut microbiota is important to investigate, as the gastrointestinal tract has been suggested as one of the major routes of infection in fish. Possible interactions between dietary components and the protective microbiota colonizing the digestive tract are discussed.     

养殖刺参溃疡病病原学研究

自2002年冬季以来,山东、辽宁等省的养殖刺参几乎每年冬天都大规模爆发溃疡病。本文研究了刺参溃疡病的特征和症状,从病参体表和体内分离出优势菌,经回归感染证实其就是引发本次刺参溃疡病的病原菌。对病原菌进行鉴定发现,该菌革兰氏染色呈阴性,电镜下观察呈短杆状,极端单鞭毛,综合研究该菌在形态、生理生化等方面的特性,确认分离到的病原菌为交替假单胞菌,交替假单胞菌作为养殖刺参的病原菌在国内外属首次报道。     

酶联免疫(ELISA)法测定水产品中呋喃唑酮代谢物AOZ的残留

采用MaxsignalTM AOZ快速检测试剂盒检测水产品中呋喃唑酮代谢物。通过对精密度、回收率和检测限等项目的测定,验证了方法的可行性。呋喃唑酮代谢物标准液在0．05ng／mL～4．5ng／mL范围内具有良好的线性,微孔板孔间变异系数为3．2％～7．7％。样品批内变异系数为5．2％～8．4％,批间变异系数为6．3％～8．9％,平均回收率为94．5％～98．4％。试剂盒的理论检测下限为0．05μg／Kg。该方法灵敏度高,重复性好,适用于水产品中呋喃唑酮代谢物残留的检测。     

信阳市主要野生水产动物重金属含量分析及质量安全评价

测定了信阳市主要野生水产动物Cd、Cr、Pb、As和Hg的含量,并根据单因子污染指数评价法对信阳市主要野生水产动物的品质进行质量安全评价。结果表明,8种信阳市主要野生水产动物的所有样品中均检出Pb和Cr,但均未检出Cd和Hg。在鲫鱼、鲤鱼、青虾和克氏原螯虾中检出As,检出率分别为60%、65.5%、55%和50%。单因子污染指数评价法表明,8种信阳市主要野生水产动物均受到不同程度的Pb污染,鲤鱼和鲫鱼受到了轻度的As污染。     

海洋SOD抗疲劳作用动物实验方法初探

超氧化物歧化酶(SOD)具有防止细胞过度氧化的生理功能,从海洋生物中提取的SOD,可用于清除运动产生的自由基,起到抗疲劳作用.本文探讨了SOD抗疲劳作用的动物实验方法,为验证SOD抗疲劳效果建立技术平台.     

水产动物基因工程抗菌肽研究及其应用前景的研究

抗菌肽是水产动物体内非特异性免疫系统的第一道防线,在抵御外来病原微生物的过程中发挥着重要作用.来源于鱼、虾、蟹等水产动物的抗菌肽杀菌作用更强,溶血效应小,种类多样化,显示出比其它种类更具优势的应用前景.介绍了一些水产动物抗菌肽的研究近况、基因工程研究进展以及转抗菌肽基因在水产动物中的研究进展,并展望了其在水产领域的应用前景.     

尼罗罗非鱼鼠李糖凝集素 (RBL-1)在非特异性细胞防御病原菌感染中的功能

为了探究鼠李糖凝集素（Rhamnose-binding lectin, RBL）在硬骨鱼非特异性细胞防御病原菌感染中的作用,本研究以尼罗罗非鱼为研究模型,首先通过分离头肾单核/巨噬细胞进行体外菌应激实验,发现在罗非鱼两种重要的致病菌-无乳链球菌（Streptococcus agalactiae）和嗜水气单胞菌（Aeromonas hydrophila）应激后,尼罗罗非鱼L-鼠李糖凝集素1（OnRBL-1）的表达量显著上调。然后,通过荧光定量PCR（qRT-PCR）检测发现OnRBL-1重组蛋白能够调节病原菌诱导细胞炎症因子的表达,包括显著抑制菌诱导的IL-6、IL-8和TNF-α的表达,和促进IL-10和TGF-β的表达。此外,通过流式细胞术检测证实OnRBL-1具有促进单核/巨噬细胞的吞噬作用,同时增强呼吸爆发水平和上调活性氧的释放。以上研究结果表明,OnRBL-1在罗非鱼单核/巨噬细胞非特异性细胞防御中发挥重要的调节作用。本研究为探讨RBL-1在硬骨鱼宿主防御病原菌感染中的功能提供了参考,并有助于完善和丰富硬骨鱼类RBL的功能和在抗菌免疫应答中的基础理论体系,具有重要的科学意义。     

采用通用引物PCR配合SSCP和RFLP技术检测鱼病病原菌

采用通用引物PCR（UPPCR）、PCR－RFLP、PCR－SSCP技术,研究快速鉴别鱼病病原菌的分子生物学诊断技术。结果发现,采用细菌16S rRNA基因保守区特异性引物,以嗜水气单胞菌、鲁克氏耶尔森菌、鳗弧菌、柱状曲挠杆菌、乙型链球菌、荧光假单胞菌等部分常见鱼病病原菌为对象,可以建立一种UPPCR技术。该技术能在保证实验条件不变的基础上,检出上述所有细菌,并还可检出大肠杆菌和双歧杆菌等非鱼病病原菌。并且认为,该法与SSCP配合即采用UPPCR－SSCP技术能较好地鉴别被检菌而用于鱼病病原菌的快速诊断。