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1.
采用石蜡组织连续切片和HE染色技术,对1~60 dph(Days post hatching)四指马鲅(Eleutheronema tetradactylum)的淋巴器官个体发育进行研究,描述了淋巴器官发育特点及组织学特征。结果显示,在盐度为9.0±0.5,水温为(28±2)℃条件下,3 dph胸腺原基出现,由4~6层未分化干细胞和淋巴母细胞样的细胞组成;胸腺发育迅速,主要由淋巴细胞填充;至25 dph皮质区和髓质区分明显,胸腺发育基本完成。3 dph头肾原基形成,由前肾管和少量造血干细胞组成;5 dph胸腺淋巴细胞向头肾迁移,头肾开始淋巴化;随着鱼体生长,造血干细胞分化成不同类型细胞;18 dph前肾管开始退化,至53 dph完全消失,头肾主要由网状内皮系统支持下的淋巴造血组织构成。7 dph脾脏原基形成,至16 dph开始淋巴化;脾脏内皮系统较头肾发达,但其发育速度较胸腺和头肾慢,淋巴细胞明显少于胸腺和头肾。研究表明,四指马鲅淋巴器官原基出现及淋巴化的顺序是胸腺、头肾、脾脏。免疫淋巴器官结构及功能尚未发育完善,可能是四指马鲅在变态期间幼体死亡率高的主要原因之一。 相似文献
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运用连续石蜡切片技术和组织学观察方法,对常规孵化出膜后1～33日龄鳜(Siniperca chuatsi)淋巴器官个体发育过程的组织学特点进行研究。结果表明,水温23～25℃时,出膜后第4天,部分仔鱼开始摄食并逐渐转入外源性营养阶段。同样水温条件下,出膜后第3天,出现胸腺原基,然后胸腺迅速淋巴化,能明显分为外区、中区和内区。鳜在出膜时已存在原肾管,原肾管前部分发育为头肾原基,由一些造血干细胞和肾小管组成;后部分发育为中肾和后肾,主要由肾小管组成。随着个体发育,头肾的淋巴细胞数量增多,肾小管数量减少,头肾逐渐由排泄器官转化为淋巴器官。出膜后第5天,观察到脾脏原基,脾脏主要由造血细胞和淋巴细胞组成,淋巴化速度较慢。至出膜后30天左右,体形和淋巴器官的发育情况基本与成鱼相似。鳜淋巴器官原基出现的顺序是头肾、胸腺、脾脏;而这些器官淋巴化的顺序是胸腺、头肾和脾脏。 相似文献
3.
《海洋渔业》2020,(1)
为了解四指马■(Eleutheronema tetradactylum)泌尿系统胚后发育的一般规律,采用石蜡组织连续切片和H-E染色技术,对1～50 dph (days post hatching)的四指马■泌尿系统胚后发育进行了研究。结果显示,四指马■前肾小管在3 dph已经形成,中间分布少量未分化干细胞;至7 dph前肾小管刷状缘明显,泌尿机能增强;15 dph前肾小管继续分化,管壁细胞结构清晰;20 dph观察到少量前肾小管退化,泌尿机能开始衰退;前肾在发育过程中未观察到肾小体形成。中肾肾小管原基在7 dph开始形成;20～25 dph中肾早期肾小体和肾小管芽形成;30 dph肾小管数量剧增,亚成熟肾小体形成,近端小管和远端小管开始区分;45 dph第一近端小管和第二近端小管开始区分,至50 dph观察到成熟肾小体;中肾有较多黑色素-巨噬细胞中心、淋巴细胞和红细胞分布,兼具造血、免疫及泌尿功能。中肾管为输尿管,始于中肾后端,并行向后合并膨大为输尿管膀胱。 相似文献
4.
为了解四指马鲅(Eleutheronema tetradactylum)泌尿系统胚后发育的一般规律,采用石蜡组织连续切片和H-E染色技术,对1~50 dph(days post hatching)的四指马鲅泌尿系统胚后发育进行了研究。结果显示,四指马鲅前肾小管在3 dph已经形成,中间分布少量未分化干细胞;至7 dph前肾小管刷状缘明显,泌尿机能增强;15 dph前肾小管继续分化,管壁细胞结构清晰;20 dph观察到少量前肾小管退化,泌尿机能开始衰退;前肾在发育过程中未观察到肾小体形成。中肾肾小管原基在7 dph开始形成;20~25 dph中肾早期肾小体和肾小管芽形成;30 dph肾小管数量剧增,亚成熟肾小体形成,近端小管和远端小管开始区分;45 dph第一近端小管和第二近端小管开始区分,至50 dph观察到成熟肾小体;中肾有较多黑色素-巨噬细胞中心、淋巴细胞和红细胞分布,兼具造血、免疫及泌尿功能。中肾管为输尿管,始于中肾后端,并行向后合并膨大为输尿管膀胱。 相似文献
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军曹鱼淋巴器官发育的形态学研究 总被引：2，自引：1，他引：1
运用组织学及组织化学的染色方法,对出膜后第1～44天(Days post-hatch,dph)的军曹鱼Rachycentron canadum头肾、脾脏和胸腺发育过程进行研究.首先观察到前肾管,3 d后,在肾管附近发现原始的造血千细胞,逐渐有红细胞和大淋巴细胞产生.之后,脾脏出现,其内毛细血管和红细胞丰富,还分布少量巨噬细胞.胸腺虽然是最后出现的淋巴器官,但是发育的非常快,内外分区明显.可以得出其淋巴器官出现顺序是头肾、脾脏和胸腺.在小淋巴细胞出现前,发现各淋巴器官内存在一些与非特异免疫机制相关的细胞,如巨噬细胞和网状细胞等.淋巴器官原基出现后开始淋巴化,其顺序是胸腺、头肾和脾脏.在采样的时间段里未观察到浆细胞,可能军曹鱼淋巴器官至此仍未发育成熟. 相似文献
6.
细鳞鲑早期发育过程中免疫器官发生 总被引：2，自引：1，他引：1
应用连续切片技术和显微观察法,对胚胎末期至仔鱼期的细鳞鲑(Brachymystax lenok)免疫器官(头肾、胸腺及脾组织)早期发育进行了系统研究。研究表明,在实验水温为10.0～16.2℃时,细鳞鲑的免疫器官原基发生及其淋巴化的先后顺序均为胸腺、头肾和脾。仔鱼出膜前5 d胸腺原基形成,出膜前1 d胸腺即出现少量淋巴细胞,仔鱼19日龄后,结缔组织和毛细血管渗入胸腺实质而形成小梁,仔鱼35日龄左右,胸腺己经分化出模糊的内区和外区;仔鱼出膜前2 d,出现头肾原基,由未分化的造血干细胞组成,仔鱼3日龄后,头肾由肾小管构成,10日龄后,组织开始淋巴化,仔鱼35～45日龄,肾小管上皮细胞开始退化,头肾内出现血窦,并进一步淋巴化,50日龄后,肾小管退化完毕,头肾主要由淋巴组织和大量血窦构成;5日龄细鳞鲑仔鱼,脾原基出现,16日龄后,脾开始淋巴化,35～50日龄,脾内建立起发达的微血管系统以及血窦结构。细鳞鲑的免疫器官分化较早,其发育速度较其他淡水硬骨鱼类相对滞后,但组织淋巴化速度较快。本研究旨在揭示细鳞鲑早期死亡率高的根本原因,为实现细鳞鲑的规模化养殖提供科学基础。 相似文献
7.
为了解中华鲟(Acipenser sinensis)免疫器官早期发育的形态和组织学特征,实验以1~300 dph中华鲟子二代的仔鱼、稚鱼和幼鱼为研究对象,使用连续石蜡切片技术和显微观察方法对免疫器官(头肾、胸腺和脾脏)的发育过程进行观察和记录。结果显示,培育水温为12.9~22.6℃时,中华鲟免疫器官原基出现的先后顺序为头肾(3 dph)、胸腺(7 dph)和脾脏(9 dph);免疫器官淋巴化先后顺序为胸腺(12 dph)、头肾(15 dph)和脾脏(33 dph)。仔鱼发育至15 dph可见头肾和胸腺间有淋巴细胞“桥”连接现象, 180 dph胸腺内可见哈氏小体结构,头肾、胸腺和脾脏内含有黑色素细胞或黑色素巨噬细胞中心(MMCs)。总体而言,中华鲟免疫器官发育具有原基出现时间早、发育速度慢和发育周期长的特点。由于仔稚幼鱼免疫系统发育不完善,建议在其培育过程中加强病害防治和早期疫苗的开发。 相似文献
8.
卵形鲳够免疫器官的早期发育 总被引：1，自引：0，他引：1
研究了卵形鲳鲹（Trachinotus ovatus）仔、稚鱼期间3种免疫器官的发生和发育过程。结果表明,3种免疫器官原基出现的先后顺序是头肾、脾脏和胸腺,出现时间分别为2日龄、3日龄和3日龄。其中,头肾的早期发育过程可分为原基形成期、造血功能发展期和泌尿功能退化期。进入稚鱼期后头肾的肾小管分布相对减少,表明头肾已不是主要的泌尿功能区。6-8日龄仔鱼脾脏中造血干细胞向红血细胞分化并产生大量未成熟红细胞。22日龄时脾脏组织体积进一步增大,内部血细胞参与血液循环。胸腺原基出现后胸腺细胞增多、体积增大,细胞嗜碱性不强。10-13日龄时胸腺细胞的嗜碱性增强,淋巴细胞开始增多,此时胸腺开始分区。20-22日龄稚鱼期结束时胸腺的内区和外区进一步分化,分区更为明显,表明胸腺进一步成熟。未发现胸腺和头肾之间淋巴细胞迁移的现象。 相似文献
9.
黄颡鱼头肾的组织发生与组织结构研究 总被引：1，自引：0，他引：1
为深入了解黄颡鱼的免疫机能,采用组织学方法,对孵化后1～48 d的黄颡鱼鱼苗头.肾的组织发生进行了观察;对5月龄幼鱼和成鱼头肾的组织结构进行了观察.结果表明,出膜后1 d,头肾仅由肾小管组成;出膜后2d,头肾小管间出现未分化的细胞团;出膜后7 d,头肾小管间出现淋巴细胞团;此后淋巴细胞及造血细胞的数量逐渐增多;出膜后26～43 d,肾小管逐渐萎缩直至完全消失,头肾完成由排泄器官向淋巴器官的转变.黄颡鱼头肾含丰富的静脉血管、血窦以及处于不同发育时期的各类免疫细胞.肾上腺组织细胞分布于头肾门静脉以及头肾组织中静脉管周边.其幼鱼头肾所含酸性颗粒细胞较成鱼头肾丰富,而成鱼头肾则具有较多的黑色素巨噬细胞,且常常在血管附近聚集形成黑色素巨噬细胞中心. 相似文献
10.
研究孵化至12月龄大黄鱼的淋巴器官如头肾、胸腺、脾的生长发育和免疫细胞数量的变化,首先应用显微与超微技术研究大黄鱼初孵仔鱼至12月龄免疫器官——头肾、胸腺与脾脏的发育。3日龄仔鱼出现头肾原基,原始造血干细胞最早被发现于头肾,很快分化成不同类型的细胞。4日龄仔鱼出现脾脏原基和胸腺原基。脾脏靠近内脏,含大量窦状隙,有丰富的毛细血管、血细胞与血小板。胸腺是最迟出现的淋巴器官,但发育较快。胸腺位于鳃腔背上角,主要由胸腺细胞(淋巴细胞)和上皮细胞组成,分为外区和内区,二者虽没有明显界限,但容易区分。研究结果还表明,随着年龄和鱼体重量的增长,胸腺、头肾和脾脏的重量均有增长的趋势,脾脏重量与体重的关系要比与年龄的关系更为密切,头肾、胸腺重量与年龄的关系要比与体重的关系更为密切。胸腺、头肾和脾脏的白细胞总数随着年龄的增长不断增加。但每毫克胸腺、头肾和脾脏内白细胞数量与年龄间线性关系不明显。头肾比脾脏淋巴化程度高。在研究中发现,血液内各细胞组成与大黄鱼月龄及季节的变化没有明显的改变。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
13.
Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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