首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
王志远  李金库  李昀  王灵钰  齐鑫  李吉方  温海深 《水产学报》2023,47(8):089104-089104
为探究ncc、nkcc基因在花鲈渗透调节中发挥的作用,实验通过全基因组鉴定、多重序列比对、系统进化树构建以及蛋白结构预测对花鲈ncc进行了鉴定及序列分析,利用实时荧光定量PCR (qRT-PCR)检测ncc和nkcc在海水、淡水花鲈鳃组织中的表达水平,利用原位杂交技术确定ncc2和nkcc1a在海水及淡水花鲈鳃中的表达位置。结果显示,从花鲈中鉴定出2个ncc基因,即ncc1和ncc2,其编码序列(CDS)长度分别为2 691和3 120bp,编码896和1 039个氨基酸,在进化上具有保守性。ncc2在淡水花鲈鳃组织中的表达量显著高于海水,而nkcc1a在海水花鲈鳃组织中的表达量显著高于淡水,ncc1、nkcc1b、nkcc2在海淡水中的表达量则无显著差异。淡水适应过程中花鲈鳃组织中的ncc2的表达量逐渐上调,而nkcc1a的表达量逐渐下调;海水适应过程则呈现相反的表达趋势。此外,原位杂交结果显示,ncc2和nkcc1a基因分别位于淡水与海水中鳃组织的相邻鳃小片间的鳃丝上皮。以上结果表明,ncc2和nkcc1a基因分别编码淡水及海水花鲈鳃中重要的Na+及Cl  相似文献   

2.
鱼鳃上氯细胞的结构与功能   总被引:2,自引:0,他引:2  
<正> 鱼类的鳃不仅是进行O_2和CO_2交换的器官,而且还参与鱼体内代谢产物的排泄、渗透压调节和酸碱的调节。这些排泄和调节都与鳃丝上皮中的氯细胞(Chloride cell)密切相关。1 氯细胞的结构 氯细胞最早是由Key和Willmer发现的。氯细胞主要分布在鳃丝上皮内。此外,还在鱼的皮肤、假鳃和鳃盖上皮中发现。氯细胞的结构十分特  相似文献   

3.
赵峰  杨刚  张涛  王妤  庄平 《海洋渔业》2016,(1):35-41
为了探讨中华鲟幼鱼进入长江口半咸水环境后,渗透压适应调节过程中鳃上皮泌氯细胞的适应性变化,将幼鱼在淡水(盐度0)和半咸水(盐度15)两种条件下驯养60 d,利用光镜和扫描电镜技术对比分析鳃上皮泌氯细胞的形态、分布与数量特征。结果表明:幼鱼鳃上皮泌氯细胞主要集中分布于鳃小片基部和鳃小片之间的鳃丝上,细胞略呈椭圆形。半咸水条件下,幼鱼鳃丝上皮泌氯细胞数量和大小显著增加,鳃小片上皮泌氯细胞数量则未发生改变,但细胞大小显著增加;而鳃丝和鳃小片上皮泌氯细胞的形态在淡水和半咸水中均未发生显著变化。扫描电镜观察发现,鳃丝上皮泌氯细胞顶膜开口的形态分为3种类型:Ⅰ型,突起型;Ⅱ型,凹陷型;Ⅲ型,深洞型。淡水条件下,顶膜开口形态多为Ⅰ型和Ⅱ型,未发现Ⅲ型存在;而半咸水条件下,顶膜开口形态以Ⅲ型为主,Ⅰ型与Ⅱ型也有少量分布。  相似文献   

4.
蓝鳃太阳鱼     
<正>太阳鱼,隶属鲈形目,淡水鱼类,原产于北美淡水水域,种类约有30多种,个体较小,常见的多为50克/尾~100克/尾。目前江浙一带和广东部分地区(如顺德)已经开始进行太阳鱼的人工养殖。顺德养殖的太阳鱼以蓝鳃太阳鱼(Lepomis macrochirus)居多。形态特征在形态上,蓝鳃太阳鱼的体型和尼罗罗非鱼有些相似。它的体形呈椭圆型,身扁背高,个体较小,普遍为80克/尾~150克/尾。外观特征最引人注目的是鳃盖后缘长有一深蓝  相似文献   

5.
铜对半滑舌鳎鳃组织结构和Na+-K+-ATPase活性影响的研究   总被引:3,自引:0,他引:3  
铜暴露后鳃的组织损伤包括:上皮肿胀、肥大增生、空泡化,鳃上皮游离,鳃小片融合,粘液细胞数量增加,杯状细胞数量减少,柱细胞体系破坏,红血球溢出或融合成瘤。氯细胞增生和鳃上皮细胞的肿大、增生使得鳃的血水交换屏障距离加大而导致鳃组织缺氧。试验结果表明,鳃暴露于Cu2 溶液后会出现离子调节功能、酸平衡调节和渗透调节功能的损伤。Na K ATPase活力随水中铜离子浓度的升高而降低,且与对照组差异显著(P≤0.05)。组织学上可以直接地反映水体中重金属污染对鱼类鳃的损伤,因此是一种水环境重金属污染监测的重要指标。Na K ATPase活力对水环境铜污染具有反应的敏感性,与铜离子浓度之间存在明显的剂量效应关系,其活力的变化可以作为水体重金属污染的生物指示器。  相似文献   

6.
不同盐度和驯养时间中华鲟子二代幼鱼鳃的显微结构变化   总被引:1,自引:0,他引:1  
采用光学显微镜和组织切片方法,研究了不同盐度和驯养时间中华鲟幼鱼鳃及鳃中泌氯细胞的结构变化特征。试验用鱼为1+龄中华鲟子二代,平均全长50.7 cm,平均体重约441.9 g。试验前在养殖池中暂养1周。试验设2个盐度梯度(10、15)组和1个对照组(淡水)。盐度驯养为将中华鲟子二代从暂养池转入盐度10海水中驯养,分别取驯养1、3、6、9、12、24、48、72、96、120、144、168、192、216、240和264 h的幼鱼各1尾用于试验;将剩下的鱼再转入盐度15海水中驯养,分别取驯养24、48、72 h的幼鱼各1尾用于试验。结果显示,在淡水组中,中华鲟子二代幼鱼鳃丝发达,细胞饱满,鳃小片宽且长。鳃丝上皮的泌氯细胞数量较少,通常靠近鳃小片基部,呈近椭圆状。与淡水组相比,盐度10组的幼鱼鳃丝主干部明显变窄,鳃小片基部区域及鳃小片上泌氯细胞的数量略有增加,胞体变大,且随驯养时间的延长,出现了明显的细胞膜间隙。幼鱼在盐度15组中鳃丝主干明显变窄变短,鳃小片也显著缩短,鳃泌氯细胞数量显著增加,主要分布在鳃小片基部,有明显的分泌腔。中华鲟子二代幼鱼能够快速适应外界水体盐度的变化,这与鳃及鳃上皮中调节渗透压功能细胞的数量和结构变化相适应。  相似文献   

7.
黄鳝(Monopterus albus)俗称鳝鱼,在鱼类分类上属硬骨鱼类、合鳃目、合鳃科,多分布于东南亚各地。在我国,除青藏高原外,各种淡水水体中均有分布。黄鳝是一种重要的经济鱼类,其肉质细嫩,营养丰富,含有多种维生素,可食部分高达65%以上,可烹调成各种美味佳肴,深受广大群众的喜爱。它又是我国传统的出口商品,畅销香港、  相似文献   

8.
近年来,在我国许多淡水养殖区域,粘孢子虫病发病率逐年增长。该病常表现为虫体侵袭鱼类的肠、肝。肾、脑等组织,或寄生于鱼类体表的鳃、鳞、鳍等部位,有的集中于鳃部近眼端,从而诱发烂鳃、赤皮、出血等疾病。病鱼特征表现为拒食,死亡率极高,给淡水养殖业带来极大危害。 鱼类粘孢子虫病历来是国际上公认的顽疾之一,至今仍无特效治疗药物及方法,主要以预防为主。首先,放养前彻底清塘,使用药物有生石灰、高锰酸钾等高氧化物,苗种下塘前使用20~30ppm高锰酸钾浸泡10-20分钟;其次,在养殖期间饲料中经常添加免疫多糖、…  相似文献   

9.
蓝鳃太阳鱼,即蓝鳃太阳鲈(Lepomis macrochirus),属鲈形目、太阳鲈科、太阳鲈属,它是一种原产于北美的淡水鱼类,我国于1987年首次从美国引进。该鱼肉质鲜美,许多名优鱼类不能与之相比,因而受到消费者的青睐。近年来养殖面积不断扩大,经济效益明显提高。观赏。蓝鳃太阳鱼体形美观,头小背高,体色艳丽,整体颜色偏蓝绿,头胸部至腹部呈淡橙红色或淡橙黄色,背部淡青灰色,间有一些淡灰黑色的纵纹,体型有些似尼罗罗非鱼。外观特征最引人注目的是鳃盖后缘长有一  相似文献   

10.
鱼类在水中呼吸主要依靠鳃来完成。鱼鳃的结构复杂又精细,梳子状的鳃瓣由鳃丝和鳃小片组成,在鳃小片中布满微血管。鱼类通过鳃丝的张合来完成呼吸的过程。除气体交换外,鳃还具有排泄废物和调节渗透压的作用。鳃很重要,但它极易被感染而致病。鱼类鳃病快速诊断和有效防治,是水产养殖生产  相似文献   

11.
12.
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   

13.
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   

14.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
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   

15.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

16.
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   

17.
18.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

19.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号