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中国对虾淋巴细胞培养中的病毒及病理观察 总被引：1，自引：0，他引：1
通过对中国对虾的淋巴器官和经过培养的养殖,海捕中国对虾的淋巴组织细胞进行电镜观察,均发现在细胞内存在一种形状为球形,有囊膜,平均直径为１３６ｎｍ的病毒。病毒分布于细胞质内,或成团存在,似为一种虹彩病毒;在养殖对虾淋巴器官及培养过的组织细胞中还发现另一种病毒,病毒粒子为正二十面体,无囊膜,平均直径为３３ｎｍ,分布于细胞质内,似为一种小ＲＮＡ病毒。 相似文献
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中国对虾淋巴组织培养中的病毒及病理观察 总被引：5，自引：0，他引：5
通过对中国对虾的淋巴器官和经过培养的养殖、海捕中国对虾的淋巴组织细胞进行电镜观察 ,均发现在细胞内存在一种形状为球形 ,有囊膜 ,平均直径为 136nm的病毒 ,病毒分布于细胞质内 ,或成团存在 ,似为一种虹彩病毒 ;在养殖对虾淋巴器官及培养过的组织细胞中还发现另一种病毒 ,病毒粒子为正二十面体 ,无囊膜 ,平均直径为 33nm ,分布于细胞质中 ,似为一种小RNA病毒。在体外培养淋巴组织过程中 ,病毒在细胞内没有明显增殖迹象。感染病毒的细胞呈现细胞核固缩 ,细胞质空泡化 ,线粒体内嵴模糊 ,粗面内质网水肿等一系列病理变化。对淋巴组织切片进行光镜观察 ,发现淋巴器官组织部分坏死 ,有些细胞核肿大 ,苏木精深染 ,严重的细胞核结构已经被破坏。 相似文献
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真鲷幼鱼狂游症病毒病原学初步研究 总被引：1，自引：0，他引：1
应用电子显微镜观察真鲷幼鱼内脏组织超薄切片。发现真鲷幼鱼脾脏存在大量病毒颗粒。病毒颗粒直径约１２０ｎｍ，呈六角形，有一层蛋白质外壳。核心主要为核心酸。病毒颗粒主要位于细胞核内。感染的细胞肿胀，比正常细胞增大５－６倍。在肠组织超薄切片中也发现少量形态相同的病毒颗粒。 相似文献
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病毒是一类比细菌还小几十倍的微生物,只能在细胞和寄主机体内增殖,需要用电子显微镜才能够看到。病毒入侵机体后,先在入侵部位的易感细胞中增殖,破坏感染细胞的合成与结构功能,导致病变坏死。并向临近的细胞和淋巴细胞扩散,形成局部的感染灶,进一步经血液侵入皮肤、肝脏、肾脏和脑等组织,导致器官病 相似文献
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氨氮促使携带白斑综合症病毒凡纳滨对虾发病及其血细胞、酚氧化酶和过氧化氢酶变化 总被引：5，自引：0，他引：5
通过白斑综合症病毒(WSSV)感染得到携带WSSV病毒的凡纳滨对虾,它们由0.05 mg/L氨氮水体进入不同氨氮浓度水体,在7 d内,1.75 mg/L,2.25 mg/L,3.00 mg/L氨氮水体内个体发生病毒病,并产生死亡。在14 d内,0.75 mg/L氨氮以及大于这一浓度水体内个体发生病毒病,并产生死亡,其中3.00 mg/L氨氮水体内死亡100%,2.25 mg/L氨氮水体内死亡80%,1.75 mg/L水体内死亡60%。在0.35 mg/L氨氮水体,7-14 d内对虾开始发病,没产生死亡。发病个体血细胞数量下降迅速,血清酚氧化酶先增高再迅速下降,其中3 mg/L氨氮水体中的携带病毒对虾只有下降。同时氨氮浓度越大,携带病毒凡纳滨对虾血清过氧化氢酶活力下降越快,越多。 相似文献
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《畜禽业》2001,(6):8
美国麻省理工学院一位研究人员近日称已研究发现了一种新的检测多种细菌和病毒的方法,可以利用经基因工程改造的细胞"快速准确”地检测到口蹄疫病毒.
美国麻省理工学院林肯实验室的托德@赖德说,这种方法"百分之百的准确”,只用大约30秒的时间就能探测出口蹄疫病毒所在.
据介绍,传统人造探测细菌和病毒的方法都不如免疫系统中自细胞来得灵敏和快速.正是基于这一点考虑,将白细胞与电子学结合制造出新型的"传感器”.赖德用水母体内能发光的细胞修改了B细胞,"修改后的细胞在遇到本身已经识别过的细菌或是病毒时,就会发亮”.
赖德说,目前已经拥有了多种能探测不同细菌和病毒的新型细胞,并称他们将在半年至一年的时间内,在包括曾遭受口蹄疫严重打击的英国郊区建立探测口蹄疫病毒的实地实验. 相似文献
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比较了3种不同的牙鲆淋巴囊肿病毒纯化方法,优化后的方法如下：剥离囊肿表面薄膜,收集内容物,匀浆后再用超声波细胞破碎仪破碎,反复冻融,650×g、1800×g差速离心,30%（W/W）蔗糖垫底超速离心（78500×g）浓缩病毒,最后蔗糖密度梯度超速离心（78500×g）纯化病毒。电镜观察发现,出现在47%～52%蔗糖密度区域的病毒带含有多量、纯净和结构一致的病毒粒子。此外,利用制备的兔抗血清对不同地区的病毒进行了免疫特性分析,Western blotting检测显示来自威海、青岛及秦皇岛3个地区的淋巴囊肿病毒反应结果是一致的,均有3条蛋白带发生反应,其分子量分别为125、66和55kDa。 相似文献
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Experimental host range and histopathology of white spot syndrome virus (WSSV) infection in shrimp, prawns, crabs and lobsters from India 总被引：5，自引：0，他引：5
K. V. Rajendran K. K. Vijayan T. C. Santiago R. M. Krol 《Journal of fish diseases》1999,22(3):183-191
Experimental studies were conducted by injecting or feeding white spot syndrome virus (WSSV) derived from infected shrimp, Penaeus monodon (Fabricius), collected from the south-east coast of India, to five species of shrimp, two species of freshwater prawns, four species of crabs and three species of lobsters. All species examined were susceptible to the virus. Experimental infections in the shrimp had the same clinical symptoms and histopathological characteristics as in naturally infected P. monodon . A cumulative mortality of 100% was observed within 5–7 days in shrimp injected with WSSV and 7–9 days in shrimp fed with infected tissue. Two species of mud crab, Scylla sp., survived the infection for 30 days without any clinical symptoms. All three species of lobsters, Panulirus sp., and the freshwater prawn, Macrobrachium rosenbergii (De Man), survived the infection for 70 days without clinical symptoms. However, bioassay and histology using healthy P. monodon revealed that crabs, prawns and lobsters may act as asymptomatic carriers/reservoir hosts of WSSV. This is the first report to suggest the carrier/reservoir capacity of these hosts through histological and bioassay evidences. Ultrastructural details of the virus in experimentally infected shrimp, P. vannamei , (Boone), were also studied. 相似文献
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The aim of this experiment was to determine the effects of dietary inclusion with mannan oligosaccharide (Bio‐Mos, Alltech, Nicholasville, KY, USA) on growth, survival, physiological and immunological conditions and gut morphology of the black tiger prawn (Penaeus monodon). Five diets supplemented with MOS at 0 g kg?1 (control diet), 1, 2, 4 and 8 g kg?1 were fed to the prawn juveniles (0.4 ± 0.06 g, total weight) for the duration of 63 days. Growth was the highest (P < 0.05) when the prawns were fed the 1 g kg?1 MOS included diet. Wet tail muscle index (Tw/B), dry tail muscle index (Td/B) and tail muscle protein (Tmp) were higher (P < 0.05) in the prawns fed MOS included diets MOS compared with the prawns fed the control diet. Total haemocyte counts (THCs) of the prawns fed MOS included diets were higher (P < 0.05) than THCs of the prawns fed the control diet. Epithelium layer and epidermal cell density of the gut of the prawns fed 1 g kg?1 and 2 g kg?1 MOS diets were better than the prawns fed the control and other MOS diets. The results imply a positive effect of dietary supplementation of 1–2 g kg?1 MOS in the culture of black tiger prawns. 相似文献
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Janet H Brown Shona McCauley Ben Ross Alan Taylor & Felicity Huntingford 《Aquaculture Research》2003,34(1):49-54
This paper describes the successful use of two tagging systems, both produced by Northwest Marine Technology Inc., on larval and postlarval giant freshwater prawns, Macrobrachium rosenbergii. Visible implant (VI) elastomer tags (a coloured liquid that solidifies under the epidermis) were used on stage XI larval prawns (mean weight 0.01 g) and postlarval prawns (mean weight 0.07 g). VI alphanumeric tags (small biocompatible plastic labels also inserted under the epidermis) were tested on postlarval prawns (from a weight of 0.5 g). Tags were inserted using clove oil as anaesthetic, and survival, mortality and growth rates of tagged animals were compared with those of controls that were handled but not anaesthetized or marked. Twenty per cent of the larval prawns (the smallest of the group) died just after tagging, but thereafter the remaining prawns survived well, as did all the tagged postlarval prawns. Visibility of the VI elastomer tags in larval prawns deteriorated with time, though 79% of marks were still visible to the naked eye 70 days after tagging. VI elastomer tags in the postlarval group remained clearly visible for up to 100 days. Visibility of the VI alphanumeric tags fell shortly after tagging, but remained adequate thereafter. Moult rates in control and tagged animals were the same in larvae with VI elastomer tags and postlarvae with VI alphanumeric tags, but the moult rate in the postlarval prawns given elastomer tags was slower than in controls. Rates of growth were similar in tagged (elastomer and alphanumeric) and control postlarval prawns, once the size‐dependent mortality of tagged larval prawns was taken into account. We conclude that VI elastomer tags could be used to mark small numbers of individual larval and immediately postlarval prawns for periods of several months, and that VI alphanumeric tags could be used to mark an unlimited number of individuals from a size of approximately 0.5 g. 相似文献
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Gregory Scott W. Guthrie Perry James W. Avault 《Journal of the World Aquaculture Society》1988,19(3):118-126
Juvenile prawns (Macrobrachium rosenbergii) were stocked at 37,050/ha and golden shiner (Noremigonus crysoleucas) fry at 321,100/ha into 16 earthen ponds at Rockefeller Wildlife Refuge, Grand Chenier, Louisiana. Four replicated treatments were tested: fed prawn monoculture, fed shiner monoculture, fed prawn and fed shiner polyculture, and unfed prawn fed shiner polyculture. The study lasted 149 days. There were no significant differences in growth between prawns fed in monoculture and prawns fed in polyculture (P > 0.05). However, fed prawns grew significantly larger (P < 0.05) than unfed prawns. Prawn survival in all treatments combined averaged 63%. Survival was significantly higher (P < 0.05) for fed prawns than for unfed prawns. Prawn yields averaged 533 kg/ha, when all treatments were combined. Yield was significantly higher (P < 0.05) for prawns grown with shiners and for prawns that received supplemental feed. Growth was significantly higher (P < 0.05) for shiners grown with fed prawns than for shiners grown with unfed prawns. Shiner survival averaged 33% and was significantly higher (P < 0.05) in monoculture than in polyculture. Yield for all ponds averaged 392 kg/ha, with no significant differences between treatments (P > 0.05). 相似文献
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Abstract— Juvenile Penaeus monodon prawns were bathed in seawater-formaldehyde concentrations of 312, 625, and 1,250 ppm for up to 6 h. The tests were conducted at concentrations in excess of those previously published, in order to examine maximum tolerance levels to formaldehyde. Physiological stress was monitored by measurement of blood glucose levels. Under controlled laboratory conditions, 12 h food deprived juvenile prawns exposed to formaldehyde concentrations of 312 ppm did not exhibit signs of stress. However, bathing in formaldehyde concentrations of 625 and 1,250 ppm, caused significant increases ( P < 0.05) in blood glucose levels after 2 and 4 h, respectively. There were no mortalities in any treatment group. In contrast, juvenile prawns from grow-out ponds bathed in 625 ppm of formaldehyde immediately after 2.5 h of transport did not exhibit significant increases in blood glucose. This may be due to their nutritional status and these results are discussed. No significant change in blood glucose levels was observed in bilaterally eyestalk ablated prawns after exposure to 1,250 ppm formaldehyde. The increase of blood glucose due to formaldehyde treatment is presumably mediated by a stress response, which includes crustacean hyperglycemic hormone (CHH), and not a result of non-specific cell lysis and death. 相似文献
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A study was conducted to 1) evaluate the compatibility of prawns (Macrobrachiurn rosenbergii) with carps, especially the effect of the common carp (Cyprinus carpio); and 2) measure the ability of prawns to utilize the foods available in manured systems. Carps used were the silver (Hypophthalmichthys molitrix), bighead (Aristichthys nobilis), grass (Ctenopharyngodon idella) and common carp (Cyprinus carpio). Four ponds (0.09 to 0.17 ha) were stocked with silver, bighead and grass carps while common carp were stocked in only two ponds. Total fish densities were 8,600/ha where four carps were stocked, but only 6,200/ha when common carp were omitted. Post-larval prawns (wt 0.116 g) were stocked at densities of 17/m2. Swine (approximately 60/ha of pond surface area) were housed on pond dikes so that fresh manure continuously entered each pond. Two lots of swine were fattened during the experimental period and loadings of swine manure were calculated based on hog size and feed consumption. Growth periods were 163 days for fish and 107 and 121 days for separate stockings of prawns. Gains in biomass by prawns averaged 714 kg/ha in ponds without common carp and 364 kg/ha in ponds containing common carp. Gains in biomass for both fish and prawns were 3,619 kg/ha (19.8 kg/ha/day) in ponds with common carp and 2,924 kg/ha (18.0 kg/ha/day) in those without common carp. Prawn survival was higher (X = 84.5% vs X = 72.5%), but final average weight of prawns was lower (2.64 vs 5.86 g) in the presence of common carp due to competition for food between common carp and prawns. Competition from carp is believed to have exerted less influence on prawn survival than predation on small prawns by larger, faster-growing prawns. 相似文献