青虾“红体病”组织病理学观察     

邵晓阳 《水产学报》2004,28(4):438-442

用连续切片的方法对患有红体病的青虾进行组织病理学研究，结果表明患病青虾鳃部、肌肉组织和肝胰腺部位病症比较明显，不同患病阶段组织变形差异显著。鳃片细胞在患病初期表现为胞质收缩，后期则细胞膨胀破裂。细胞内物质外溢，细胞边缘界限不完整；肌肉组织在后期出现肌纤维束之间间隙，且部分肌纤维有断裂的现象；中期肝小叶间隔出现空隙和腺细胞变形，在后期则表现为小叶溃烂。造成青虾因红体病死亡的原因，初期主要是因为鳃片的组织病变导致呼吸困难，进而造成青虾生理异常；后期主要是因为肝胰脏的溃烂造成消化功能全面丧失。  相似文献   

乳山湾东流区细菌数量的分布及与环境因子关系的研究   总被引：1，自引：0，他引：1  

陈碧鹃  李秋芬  陈聚法  马绍赛  崔毅  辛福言 《海洋水产研究》1997,(2)

根据1995年6～9月对乳山湾东流区的微生物调查资料，研究了乳山湾东流区海水及底泥中细菌和弧菌量的变化及其与环境因子的关系。结果表明，该海域海水中细菌和弧菌的数量变化与温度的变化相一致，6月中旬～8月中旬，细菌数量增长比较缓慢，8月中旬开始，细菌数量增长较快，到8月底，达到最高值，异养菌为5．71×106cell／mL，弧菌为2．1×104cell／mL。而后，随着温度的下降，水中的细菌量逐渐减少。滩涂底泥中，细菌和弧菌的数量均比海水中细菌高l～2个数量级。  相似文献   

Changes induced by osmotic stress in the morphology,biochemistry, physiology,anatomy and stomatal parameters of almond species （Prunus L. spp.） grown in vitro     

Shakiba Rajabpoor  ;Soghra Kiani  ;Karim Sorkheh  ;Farahnaz Tavakoli 《林业研究》2014,25(3):523-534

We investigated the influence of different levels of osmotic stress on growth and development in selected wild almond species(eight Prunus spp.) grown in vitro. The study, while endorsing the efficacy of in vitro screening of auxiliary buds of wild almond for osmotic stress tolerance, showed species variability in its response to osmotic stress. Osmotic stress reduced growth and development of all the species. However, the putative tolerant Prunus spp. showed better performance than the putative susceptible genotypes. On average there was an 80% decrease in shoot dry weight at-1.2 MPa. Reduction in shoot weight was more common in osmotic stress-susceptible species in the section labeled ‘Euamygdalus'. The tolerant Prunus species produced smaller changes in biochemical responses than the sensitive cultivars for malondialdehyde content, catalase activity, relative permeability of protoplast membranes, and net photosynthetic rate. The tolerant species maintained cell integrity better than drought sensitive species. Wild almond species in the section labeled ‘Spartioides'(Prunus arabica(Olivier) Neikle, Prunus glauca (Browicz) A.E. Murray, Prunus scoparia Spach) and ‘Lycioides'(Prunus lycioides Spach, Prunus reuteri Bossi. et Bushe) were best adapted to osmotic stress. Increase in chlorophyll concentration and leaf thickness under high osmotic stress can be considered as preliminary selection parameters for osmotic stress tolerance in Prunus spp. The study confirmed the efficacy of the in vitro method for screening of large number of genotypes for osmotic stress tolerance in wild almond species.  相似文献   

广东适生樱花及其园林应用   总被引：4，自引：2，他引：2  

叶超宏  陈家艳  胡晓敏  张丹丹  刘湘源 《广东园林》2014,(5):59-61

在对樱花作系统调查、引种、筛选和试种的基础上,推介适合广东地区种植的‘中国红’、‘广州’樱、和‘富贵’樱等5种适应性强、观赏价值高的樱花品种,重点介绍其品种特征、生态习性、观赏特性、繁殖栽培及园林应用。  相似文献   

Delivery of HUFA, probionts and biomedicine through bioencapsulated Artemia as a means to enhance the growth and survival and reduce the pathogenesity in shrimp Penaeus monodon postlarvae     

G. Immanuel  T. Citarasu  V. Sivaram  M. Michael Babu  A. Palavesam 《Aquaculture International》2007,15(2):137-152

One of the major problems in the shrimp culture industry is the difficulty in producing high-quality shrimp larvae. In larviculture, quality feeds containing a high content of highly unsaturated fatty acids (HUFA) and ingredients that stimulate stress and disease resistance are essential to produce healthy shrimp larvae. In the present study, Penaeus monodon postlarvae (PL15) were fed for 25 days on an unenriched Artemia diet (control; A) or on a diet of Artemia enriched with either HUFA-rich liver oil of the trash fish Odonus niger (B), probionts [Lactobacillus acidophilus (C1) or yeast-Saccharomyces cerevisiae (C2)] or biomedicinal herbal products (D) that have anti-stress, growth-promoting and anti-microbial characteristics. P. monodon postlarvae fed unenriched Artemia exhibited the lowest weight gain (227.9 ± 8.30 mg) and specific growth rate (9.95 ± 0.05%), while those fed the HUFA-enriched Artemia (B) exhibited the highest weight gain and specific growth rate (362.34 ± 12.56 mg and 11.77 ± 0.08%, respectively). At the end of the 25-day rearing experiment, the shrimp postlarvae (PL40) were subjected to a salinity stress study. At both low and high (0 and 50‰) salinities, the group fed the control diet (A) experienced the highest cumulative mortality indices (CMI) 935.7 ± 2.1 and 1270.7 ± 3.1, respectively. Those fed diet D showed the lowest stress-induced mortality, and CMI were reduced by 31.1 and 32.3% under conditions of low and high salinity stress, respectively. A 10-day disease challenge test was conducted with the P. monodon postlarvae (PL40–PL50) by inoculating the shrimp with the pathogen Vibrio harveyi at the rate of 10⁵–10⁷ CFU/ml in all rearing tanks. P. monodon postlarvae fed probiont-encapsulated Artemia diets (C1 and C2) exhibited the highest survival (94.3 and 82.3%, respectively) and lowest pathogen load (V. harveyi) in hepatopancreas (5.2 × 10² ± 9.0 × 10 and 4.6 × 10² ± 9.0 × 10 CFU g⁻¹, respectively) and muscle (2.0 × 10² ± 6 × 10 and 1.7 × 10² ± 8.6 × 10 CFU g⁻¹, respectively) tissues. The shrimp that were fed the unenriched Artemia (Control; A) showed the lowest survival (26.33%) and highest bacterial load in the hepatopancreas (1.0 × 10⁵ ± 5 × 10³ CFU g⁻¹) and muscle (3.6 × 10⁴ ± 6 × 10² CFU g⁻¹). The shrimp fed the herbal product (D)-enriched Artemia also exhibited enhanced survival and reduced V. harveyi load in the tissues tested compared to the control diet (A) group. The results are discussed in terms of developing a quality larval feed to produce healthy shrimp larvae.  相似文献   

A review of extracellular virulence product of Vibrio species important in diseases of cultivated shrimp   总被引：2，自引：0，他引：2  

Gabriel Aguirre-Guzmán  Humberto Mejia Ruíz  & Felipe Ascencio 《Aquaculture Research》2004,35(15):1395-1404

Shrimp aquaculture is an important industry that experiences significant losses from Vibrio species, especially at the larval and juvenile stages. Proteinaceous virulence factors, including alkaline proteases, metalloproteases, cysteine proteases and alkaline serine proteases, have been identified as important elements in Vibrio pathogenesis. This review summarizes current knowledge regarding the principal pathogenic Vibrio species in shrimp, with emphasis on relevant exotoxins and their modes of action, principal characteristics and molecular database. This pathogenic factors and their relation with other molecules produced by microorganisms may be help to understand the virulence mechanisms present in Vibrio strain.  相似文献   

Bacterial flora associated with the giant freshwater prawn Macrobrachium rosenbergii, in the hatchery system     

Bob Kennedy 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1156-1167

The objective of this study was to understand the microbial flora associated with the hatchery system of giant fresh water prawn, Macrobrachium rosenbergii during an entire rearing cycle. Bacteriological and physico-chemical analysis was done for different samples of water, larvae, and Artemia. The total bacterial load in well water, seawater and inlet water varied from 10¹ to 10⁵ cfu ml^− 1 with higher counts seen in larval rearing tank (LRT) water. The Vibrio count ranged between 10¹ to 10³ cfu ml^− 1. Larval samples harboured a bacterial load of 10⁶ to 10⁷ cfu/10 larvae. The bacterial load in Artemia hatching water ranged from 4.90 × 10⁴ to 5.63 × 10⁶ cfu ml^− 1 while Artemia had a load ranging from 1.08 × 10⁷ to 2.09 × 10⁹ cfu g^− 1. Vibrio count in the LRT water ranged from 10¹-10³ cfu ml^− 1 while the count in larvae ranged from 10² to 10⁴ cfu/10 larvae. The bacterial genera were predominantly Gram-negative and comprised of Aeromonas spp., Pseudomonas spp., Vibrio spp. and Bacillus spp. and non-spore formers (NSF) were the dominant Gram-positive bacteria. This study documents the bacterial flora associated with Macrobrachium hatchery system during a regular normal run. Knowledge of the qualitative and quantitative aspects of bacterial flora in the hatchery would help to understand disturbances, if any, brought about during disease outbreaks.  相似文献   

台湾输入甲鱼中检出O1群霍乱弧菌   总被引：1，自引：0，他引：1  

吴玉娟  ;孔繁德  ;徐淑菲  ;叶妍妍  ;龚艳清  ;王仍瑞 《经济动物学报》2014,(2):100-103

将甲鱼体表涂抹物在碱性蛋白胨水中进行增菌培养,分离单菌落后分别用基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)、血清学方法及PCR进行鉴定,结果从台湾输入大陆的甲鱼中检出O1群稻叶型霍乱弧菌一株,不含ctx基因和toxR基因。为此,应加强水产品尤其是甲鱼的监测工作,防止霍乱弧菌在不同地区间的传播和流行。  相似文献   

鹤蕉种质资源抗寒性和农艺性状的鉴定与评价     

徐世松  杨光穗  黄少华  张志群  尹俊梅 《热带生物学报》2014,5(4)

针对抗寒性、花期和观赏特性等几个农艺性状,对引进的67个鹤蕉品种进行了连续3年的大田圃鉴定与评价,筛选出适合在海南不同区域栽培的8个有应用价值的品种。旨在为鹤蕉的品种改良、栽培和开发利用提供参考。  相似文献   

甘肃甘南野生羊肚菌rDNA的ITS序列分析     

王龙  秦鹏  王生荣  赵玉卉 《草原与草坪》2014,(6):41-44

根据形态学特征挑选了7株采自甘肃甘南境内的野生羊肚菌,应用rDNA-ITS序列进行了比对技术分析。结果表明,7株野生羊肚菌归属为4个种：粗柄羊肚菌Morchellav crassipes、羊肚菌M.esculenta、黑脉羊肚菌M.angusticeps和高羊肚菌M.elata。根据分子系统树发现,粗柄羊肚菌和羊肚菌属于黄羊肚菌类群,而黑脉羊肚菌和高羊肚菌属于黑羊肚菌类群。  相似文献