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1.
刺激隐核虫生活史的光镜观察 总被引：5，自引：0，他引：5
本文对寄生于海水硬骨鱼体表组织的纤毛虫刺激隐核虫(Cryptocaryonirritans)的生活史进行了描述。该寄生虫生活史分3个阶段,即滋养体,包囊体和幼虫。滋养体主要营寄生生活。成熟的滋养体离开宿主后,在数小时内就发育成包囊体。包囊体的特点是具多层结构的囊壁,而且此阶段虫体的繁殖方式为不等分裂。每个成熟的包囊平均可形成273±64个幼虫。由于囊壁坚硬,幼虫游离后,包囊壁仍保持原样。进入水体的幼虫游动极快,不摄食,一旦遇到合适的宿主即侵入,并在宿主体内发育成滋养体。文中还将结果与淡水多子小瓜虫生活史进行了比较。 相似文献
2.
报道了牙鲆养殖过程中发生的体表溃烂综合症的病理组织变化。该病的病原有盾纤类纤毛虫指状拟舟虫和致病菌兔莫拉氏菌。指状拟舟虫不仅寄生于牙鲆体表皮肤、鳍 ,亦可侵入腹腔、肾脏、肌肉、心脏甚至脑。兔莫拉氏菌大量寄生于心脏血液中 ,随血液循环至各组织器官 ,引起牙鲆肝脏、肾脏及脾脏组织病变。指状拟舟虫和兔莫拉氏菌共同导致牙鲆死亡。 相似文献
3.
论述了迄今为止所发现的由海水鱼类寄生甲壳类的寄生引起的宿主鱼类的血液，生长，生理功能和行为的病理变化特点；描述了寄生虫对寄主组织和体表造成损伤和破坏所形成的组织病理特性；此外对现有的鱼类甲壳动物病的防治药物和方法进行了评述。 相似文献
4.
血卵涡鞭虫在养殖锯缘青蟹中的寄生 总被引：5，自引：0，他引：5
利用光镜和电镜对2005年9月浙江三门湾地区某养殖场发生的养殖锯缘青蟹规模性死亡病蟹进行观察，并对病原进行分子生物学鉴定。组织病理学研究发现，病蟹蟹体消瘦，肌肉白浊，头胸甲内可见大量乳白色液体，血淋巴细胞的量急剧减少，代之以大量寄生原虫，该原虫在病蟹的肝胰腺、鳃、心脏、肌肉等部位大量寄生，引起这些组织发生以坏死为主的变质性病变。电镜下，乳白色液体及病变组织内可见大量寄生虫体，其形态特征、内部结构及宿主表现的症状，与血卵涡鞭虫相类似。采用Small等^[5]的血卵涡鞭虫ITS特异引物，扩增出分子量为300bp左右的条带，并对其进行了测序及序列相似性比较，确定该寄生原虫为一种血卵涡鞭虫Hemntodinium sp。血卵涡鞭虫是海水甲壳类的重要病原寄生虫，我国尚未有该寄生虫病的研究报道，文中首次发现其在养殖锯缘青蟹中的寄生，为靳一步研究该寄生虫病积累了资料。 相似文献
5.
血卵涡鞭虫是一类主要感染海产甲壳类的致病性寄生性甲藻。近年来,该寄生性病原在我国沿海主要经济蟹类养殖区域流行性发病,给当地蟹类养殖业造成了严重经济损失。为厘清血卵涡鞭虫的生活史形态,了解宿主的病理损伤机制,本文通过血涂片法和HE染色法系统研究了感染过程中该寄生虫的形态变化和宿主的组织病理变化。结果表明,血卵涡鞭虫在感染过程中经历丝状滋养体、单核/双核/多核滋养体、团聚体、蛛网状滋养体、孢子前细胞及孢子等不同生活史阶段。感染导致三疣梭子蟹发生系统性病理变化,肝胰腺、心脏、鳃、肌肉等器官和组织在不同感染阶段均发生相应程度的组织病理变化,主要表现为体细胞破损或坏死、细胞间隙模糊、疏松结缔组织充斥大量寄生虫细胞。最终由于寄生虫在宿主主要器官组织间隙内大量增殖,导致重度感染的梭子蟹器官或组织功能破坏、丧失而死亡。 相似文献
6.
海水鱼类白点病的病原虫为刺激隐核虫(Crypto caryon irrtans Brown),多寄生在海水硬骨鱼类的皮肤、鳃、鳍、眼膜等上皮组织中,是一种肉眼可见的海产纤毛虫类。因为此虫大量寄生在海鱼的鳃组织等部位,而使鳃组织受到破坏,失去正常功能,引起病鱼窒息死亡。在一般情况下,用药物治疗又很难在 相似文献
7.
鲈鱼的鳃寄生车轮虫病及扫描电镜观察 总被引：1，自引：0，他引：1
报道鲈鱼的鳃寄生车轮虫病及病理组织的扫描电镜观察。病原鉴定为 :直钩车轮虫、杜氏车轮虫、日本车轮虫、劳牧小车轮虫及简单两分虫 5种车轮虫科纤毛虫 ,其中数量上占优势的为直钩车轮虫。扫描电镜观察结果表明 ,鳃寄生车轮虫可对宿主的上皮组织产生明显的机械性损伤并造成鳃丝粘液分泌增多及炎症反应。文中就海水养殖鱼类及野生鱼类由车轮虫寄生造成的危害及防治途径做了探讨。 相似文献
8.
依据干银法和蛋白银染色法研究了山东沿海养殖鱼类的 4种寄生车轮虫属纤毛虫 :直钩车轮虫、杜氏车轮虫、日本车轮虫及小袖车轮虫 ,其中直钩车轮虫为我国的新记录。作者对采自不同宿主的直钩车轮虫种群的形态学特征进行了比较描述 ,对所涉车轮虫的形态学、宿主、分布、流行情况及危害程度等做了综合报道 相似文献
9.
通过现场取样、显微镜检、细菌培养、组织病理、电镜观察以及PCR检测等研究手段,对2008年9月浙江省舟山市普陀区某梭子蟹养殖塘混养的脊尾白虾"白浊病"进行了系统的病原学研究。结果表明,病虾体色发白,反应迟钝,血淋巴液呈浊白色,严重患病白虾血淋巴中的血细胞几乎没有或者极少,代之以大量与血细胞形似的寄生虫;组织病理切片及电镜观察发现,病虾心脏、肝胰腺、肌肉、鳃部等组织寄生有大量单细胞寄生虫,该寄生虫虫体形态特征、显微结构及宿主临床症状与本实验室之前研究报道的感染三疣梭子蟹和锯缘青蟹的血卵涡鞭虫类似;采用已建立的针对血卵涡鞭虫ITS1基因的引物对"白浊病"病虾的血淋巴样品进行PCR检测,可扩增出585bp左右的特异条带。综合以上研究结果,确定该寄生虫为血卵涡鞭虫(Hematodinium sp.)。有关脊尾白虾感染该寄生虫的报道在国内外尚属首次。 相似文献
10.
依据干银法和蛋白银染色法研究了山东沿海养殖鱼类的4种寄生车轮虫属纤毛虫: 直钩车轮虫、杜氏车轮虫、日本车轮虫及小袖车轮虫, 其中直钩车轮虫为我国的新记录.作者对采自不同宿主的直钩车轮虫种群的形态学特征进行了比较描述, 对所涉车轮虫的形态学、宿主、分布、流行情况及危害程度等做了综合报道. 相似文献
11.
The isopod Nerocila depressa is present on 54% of the market-sized white sardines (Sardinella albella) caught from an estuary in the Trat province of Thailand. The ventral part of the body, especially the upper pectoral fin, was the area most frequently infected by this parasite. Parasite length was positively correlated with fish length, which suggests that the parasites attach to the fish at a young age. At the site of attachment, the parasites erode the epidermis, dermis and muscular tissue of the Sardinella. Such pathology may cause mortality in many fish. Infestation of this parasite was proportional to the weight of the fish. This study reports a new host for N. depressa attachment and is the first report of S. albella infestation in the Trat province where other known host fish species are cultured. 相似文献
12.
香鱼(Plecoglossus altivelis)是名贵洄游性鱼类,由于高密度养殖等因素导致病害频发。类志贺邻单胞菌广泛存在于养殖水环境中,给香鱼养殖业造成严重经济损失。对患体表溃疡病的香鱼进行病原分离和鉴定,从患病鱼体表和肠道组织中分离到一株优势菌(NH21),其菌落低突,边缘光滑,表面湿润。革兰氏染色结果显示NH21为革兰氏阴性菌,菌形态为短杆状,端圆。经生化特性和16S rDNA序列分析鉴定为类志贺邻单胞菌(Plesiomonas shigelloides)。回归感染后,香鱼呈现与发病鱼相似的症状,皮肤、肌肉溃烂并伴有周围皮肤充血,组织切片可观察到病鱼肌纤维断裂,周围红细胞、炎性细胞浸润;鳃丝和鳃小片中红细胞增多;肝细胞核呈空泡,部分细胞核染色质边集;脾脏内包细胞增多,红细胞呈梭形;肠黏膜上皮细胞脱落。经计算其半致死量LD50为1.99×107 CFU/mL。25种抗生素的药敏试验显示NH21菌株对阿奇霉素、头孢氨苄、新生霉素、多粘菌素B、头孢西丁、呋喃唑酮6种抗生素敏感。检出NH21菌株毒力基因9个,耐药基因8个。综合分析表明,分离菌株NH21为类志贺邻单胞菌属,是本次香鱼体表溃烂病病原菌,研究结果为香鱼出现类似病症的预防和治疗提供了基础资料。 相似文献
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14.
Bivalve populations from inshore waters often accommodate a diverse trematode fauna that may have a variety of effects on host specimens. In particular, larval trematodes that grow or reproduce within their host are known to be severe pathogens, whereas trematodes utilising bivalves only for encystment are thought to be relatively benign. Yet this may depend on the environmental conditions, and it can be expected that such trematodes in concert with other stress agents can be detrimental to host organisms. To examine the impact of such larval trematodes on hosts subjected to stress, we studied the digenetic trematode Himasthla elongata and one of its second intermediate hosts, the bivalve Cerastoderma edule. Experimentally infected cockles and non-infected cockles were exposed to oxygen depletion, whereupon we measured their burrowing ability and survivorship. After 30 h of hypoxia, the survival of infected cockles was significantly reduced compared to non-infected cockles, whereas no effect of parasites on cockles under normoxic conditions was found. In addition, parasites tended to reduce the burrowing ability of cockles exposed to hypoxia but the effect was not clear. The effect of parasites and possible ecological consequences are discussed and it is suggested that the combined effects of parasites and oxygen deficiency may explain some hitherto unexplained cases of mass mortalities in bivalve populations. 相似文献
15.
采用常规石蜡切片法,对海神草(Cymodocea rotundata)营养器官的组织学进行研究。结果表明:海神草的根、茎、叶均具有发达的通气组织,根由表皮、皮层和维管柱三部分组成,内皮层中有凯氏带且六面加厚结构。茎由表皮、基本组织和维管组织三部分组成,维管组织有1束中央维管束和数束外环维管束,维管束为有限外韧维管束,有气隙分布。叶由表皮、叶肉和叶脉三部分组成,上下表皮均由单层细胞构成,排列规则无胞间隙,其外壁覆盖一层连续的角质层,无气孔但分布有类泡状细胞,表皮细胞中富含叶绿体,是光合作用的主要部位。本文还讨论了海神草营养器官与海洋沉水生活相适应的结构特征。 相似文献
16.
HUANG Xiaohang LAM Patrick P L LIN Xuezheng LIU Chenlin BIAN Ji GAISANO Herbert 《海洋学报(英文版)》2007,26(1):159-164
1 IntroductionSecretion is a basic function of all living organ-isms. In fish, like in mammals, neurotransmitters,hormones, enzymes and other macromolecules aresecreted in several neuronal, neuroendocrine and ex-ocrine organs and tissues located in brain,… 相似文献
17.
热带海洋珍珠贝类立克次体病研究 Ⅳ.组织细胞病理学研究 总被引：4，自引：0，他引：4
类立克次体（RLO）对大珠母贝和合浦珠母贝具有强烈的致病性,引起基本一致的病理变化．在急性坏死破坏期内,RLO导致外套膜、鳃、消化管、肝胰腺、生殖腺腺管及全身血管内皮系统等多器官组织的变性坏死,使器官组织结构的完整性遭到破坏,破坏程度与RLO包涵体的数目密切相关,而细胞的破坏与细胞内RLO的生长发育及繁殖到大量数目密切相关．鉴于此,将RLO引起的珍珠贝病称为类立克次体病（RLO病）．RLO病呈急性变质性炎症和慢性增生性炎症病理,在前者细胞呈现崩解性坏死、溶解性坏死和退变性坏死;在后者存在实质细胞增生和纤维母细胞增生为纤维细胞并形成纤维化．根据炎症病理的发展过程,RLO病可分为急性坏死破坏期和慢性增生修复期． 相似文献
18.
Host‐dependent differences in resource use associated with Anilocra spp. parasitism in two coral reef fishes,as revealed by stable carbon and nitrogen isotope analyses 
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下载免费PDF全文 The role of parasites in trophic ecology is poorly understood in marine ecosystems. Stable isotope analyses (SIA) have been widely used in studies of trophic ecology, but have rarely been applied to study the role of parasites. Considering that some parasites are associated with altered host foraging patterns, SIA can help elucidate whether parasitism influences host trophic interactions. French grunt (Haemulon flavolineatum), an abundant Caribbean coral reef fish, contributes greatly to trophic connectivity. They typically depart the reef at dusk, feed overnight in seagrass beds, and return to the reef at dawn. The large parasitic isopod Anilocra haemuli commonly infects French grunt, and infected fish are less likely to complete their diel migration, and are in poorer condition than uninfected conspecifics. Brown chromis (Chromis multilineata) are diurnally feeding planktivores and infection by Anilocra chromis does not influence host condition. To determine if Anilocra infection influences host diet and foraging locality, we conducted stable carbon and nitrogen isotope analyses on scale, muscle, heart and gill tissues of infected and uninfected French grunt and brown chromis. We determined that all French grunt had δ13C values representative of seagrass habitats, but infected French grunt were significantly enriched in 13C and 15N compared to uninfected conspecifics. This suggests that compared to uninfected conspecifics, infected French grunt forage in seagrass, but on isotopically enriched prey, and/or are in poorer condition, which can elevate δ13C and δ15N values. For brown chromis, infection did not significantly influence any δ13C and δ15N values; hence they all foraged in the same environment and on similar prey. This is the first study to use SIA to examine differences in resource use by Caribbean coral reef fishes associated with parasitism and to evaluate how closely related parasites might have host‐dependent effects on host trophic ecology. 相似文献
19.
Juerg M. Brunnschweiler 《Marine Ecology》2006,27(1):89-94
It is not known whether sharksuckers have positive or negative effects on their hosts, partly because this association is difficult to study in free‐ranging fish. I observed the behaviour of sharks with and without sharksuckers, to determine whether the hosts actively avoid sharksuckers. Wild blacktip sharks, Carcharhinus limbatus, took evasive actions when sharksuckers, Echeneis naucrates, attached to them, presumably to escape from skin irritation or hydrodynamical drag caused by the sharksuckers. Sharksuckers were most often attached to the belly or back of the shark, and sharks reacted most strongly to sharksuckers on their heads, sides, and dorsal fins. Observations of two captive bull sharks, Carcharhinus leucas, indicated that swimming speed increased when sharksuckers were attached. This paper supports the hypothesis that sharksucker attachment irritates sharks, and that the relationship between the two is best viewed as a subtle host–parasite interaction. 相似文献