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1.
为了解NR5a2在中华鳖(Pelodiscus sinensis)性腺分化过程中的作用,通过RACE技术克隆获得中华鳖NR5a2 cDNA。结果显示:该基因序列全长为2 674 bp,开放阅读框为1 608 bp,编码535个氨基酸,5′非编码区长度为40 bp,3′非编码区长度为1 026 bp。生物信息学分析表明该基因编码的蛋白质分子质量为60.5 ku,等电点为8.57,具有保守的ZnF-C4结构域和HOLI结构域。氨基酸多重序列比对分析表明中华鳖NR5a2基因与西部锦龟(Chrysemys picta bellii)的相似性最高,其次是原鸡(Gallus gallus)。系统进化分析表明中华鳖NR5a2与西部锦龟的亲缘关系最近。实时荧光定量PCR结果表明NR5a2在中华鳖不同组织中均有表达,且卵巢组织中的表达量显著高于精巢组织。31.5℃孵化条件下,不同发育时期的中华鳖胚胎组织中发现NR5a2基因在17期时表达量达到最高,随后显著下降。结果表明NR5a2可能参与中华鳖的性别分化。 相似文献
2.
G蛋白偶联雌激素受体（Gper）是一种膜雌激素受体,介导雌激素的非基因组途径。为研究G蛋白偶联雌激素受体基因（ cDNA全长序列,利用qRT-PCR分析其在不同组织及胚胎不同发育阶段的性腺中的表达模式,并通过来曲唑（letrozole）和Gper抑制剂G-15处理雄鳖初步分析Gper在精巢中的作用。结果显示,中华鳖 cDNA序列全长2023 bp,包含705 bp 5''非编码区、241 bp 3''非编码区和1077 bp开放阅读框,编码358个氨基酸,其氨基酸序列上有7个跨膜结构域和Asp-Arg-Tyr（DRY）三联体结构,基因编码蛋白分子量为41.084 kD,等电点为6.844。表达量变化呈相同趋势：16期表达量最高,随着性腺分化过程表达量显著降低。Letrozole处理组中2表达量明显升高;G-15处理组精巢中,精子发生与促细胞凋亡相关基因表达量显著升高。结果表明,可能参与中华鳖性腺分化早期过程,并调控雄性生殖细胞增殖。 相似文献
3.
为了解GnRH基因在中华鳖(Pelodiscus sinensis)性腺和胚胎发育过程中的表达特征,采用cDNA末端快速扩增(RACE)技术从中华鳖全脑中获得与生长生殖调控密切相关的GnRH1基因全长cDNA,并运用实时荧光定量PCR(qRT-PCR)技术检测GnRH1在成鳖不同组织和胚胎发育时期的表达水平。结果显示:中华鳖GnRH1基因cDNA全长546 bp,其中5′非编码区(5′UTR)99 bp,3′非编码区(3′UTR)168 bp,开放阅读框(ORF)279 bp,编码92个氨基酸,分子质量为10.23 ku,理论等电点pI为5.65,具有N端信号肽(1~23 aa)、核心十肽区域(24~33 aa)、断裂位点GKR(34~36 aa)及相关肽区域(37~92 aa),符合GnRH蛋白典型结构特征。系统进化树结果显示,中华鳖GnRH1基因和绿海龟(Chelonia mydas)、墨西哥箱龟(Terrapene carolina mexicana)及西部锦龟(Chrysemys picta bellii)GnRH1基因聚为一支。qRT-PCR结果表明,GnRH1基因在中华鳖雌雄个体的8个组织中均有表达,在脑和性腺组织中高表达,且具有性别差异,雄性中华鳖中的表达显著高于雌性(P<0.05);在10个胚胎发育时期均表达,且随发育时间的后移,表达量显著增加,在第16期达到峰值。GnRH1基因可能在中华鳖生长及性腺分化中具有重要作用。 相似文献
4.
利用逆转录聚合酶链式反应(RT-PCR)和cDNA末端快速扩增(RACE)等方法,克隆获得剑尾鱼卵黄蛋白原C(Vg C)基因的全长cDNA序列。剑尾鱼Vg C基因cDNA序列全长4 011 bp,其5′非编码区包含12 bp和3′非编码区包含246 bp;含有一个3 753 bp的开放阅读框(ORF),编码1 250个氨基酸,推测其编码氨基酸分子量大小为141.7 ku,编码氨基酸序列与其他鱼类卵黄白原C编码氨基酸序列相似性在44%～85%。荧光定量PCR结果显示,Vg C在剑尾鱼肝脏中表达量最高,脾、肾、卵巢中有微量表达,脑、肌肉、鳃中几乎没有检测到表达;对不同时间暴露在雌激素中剑尾鱼肝脏进行实时荧光定量PCR表达分析的结果表明,Vg C在剑尾鱼肝脏中第5天表达量最高,随后降低,第9天后维持相对较低的表达量。研究首次克隆了剑尾鱼Vg C基因全长cDNA序列,并对Vg C在剑尾鱼体内表达组织器官分布及雌激素诱导后不同时间表达谱进行了初步研究,为剑尾鱼生殖生理及环境污染物监测应用等不同领域研究打下重要基础。 相似文献
5.
为探索R-spondin1(Rspo1)基因在雌核发育三倍体鱼淇河鲫性别决定与分化过程中的作用,本研究利用RACE技术克隆Rspo1基因cDNA序列,同时分析它的时空表达模式,并检测芳香化酶抑制剂Letrozole及高温养殖诱导性逆转下它在性腺中的表达情况。将扩增的PCR产物经亚克隆测序、拼接后获得淇河鲫Rspo1 cDNA序列,长1 243 bp(MH243761),包含5′非编码区318 bp,3′非编码区127 bp和开放读码框798 bp,共编码265个氨基酸残基。氨基酸序列比对及系统进化分析结果显示,淇河鲫Rspo1与其他鲤科鱼类同源性较高,与哺乳类、爬行类等脊椎动物同源性相对较低;组织分布检测结果显示,Rspo1基因在淇河鲫各个组织中均有表达,其中肌肉组织表达量最高,卵巢次之,而在脾脏、肾脏、心脏组织中表达量较低;在胚胎发育过程中Rspo1的表达量在未受精卵与受精卵中无差异,随着胚胎发育而降低,神经胚期最低,从尾芽期至出膜期又逐步升高。胚后阶段,Rspo1在性腺中的表达量从淇河鲫性别决定与分化关键时期(孵化后20 d)开始上调。Letrozole处理或高温养殖引起的性逆转中,Rspo1在性腺中表达量升高。研究表明,淇河鲫Rspo1作为一个母源性因子可能在卵巢分化与维持中起到一定作用,同时它可能也参与精子发生过程。 相似文献
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《水产科学》2019,(6)
通过同源克隆和cDNA末端快速克隆技术扩增获得狭温热带鱼类虎皮鱼热激蛋白70(PtHsp70)基因的cDNA序列,BLAST比对分析基因序列同源性,预测其编码氨基酸序列和结构,实时荧光定量PCR技术分析虎皮鱼PtHsp70基因组织特异性表达谱和低温胁迫下PtHsp70基因的表达模式。研究结果表明,PtHsp70基因cDNA序列全长2317 bp,其中5′非编码区120 bp,3′非编码区266 bp,编码区1932 bp,对应的开放阅读框为121～2052 bp,预测编码643个氨基酸。PtHsp70基因mRNA在成年虎皮鱼不同组织中表达水平依次为肝脏肌肉鳃脑,其中肝脏PtHsp70基因本底表达水平显著高于其他组织(P0.01),表明其在肝脏中具有重要的生物学功能。而随温度降低,肝脏PtHsp70基因表达水平呈先降后升的趋势,表明肝脏PtHsp70基因参与虎皮鱼应对低温胁迫的过程;随温度降低,虎皮鱼脑、鳃和肌肉组织PtHsp70基因mRNA水平显著上调(P0.01),说明低温胁迫诱导PtHsp70基因mRNA表达。本研究克隆并鉴定了PtHsp70基因序列和组织表达谱,分析了低温胁迫下PtHsp70基因表达模式,研究结果显示,狭温热带鱼类虎皮鱼的PtHsp70基因具有组织特异性和温度诱导型表达特征。研究发现,PtHsp70基因在响应低温胁迫过程中具有重要作用,具有作为虎皮鱼低温胁迫分子标志物的潜能。 相似文献
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为了探究生长激素释放激素(growth hormone releasing hormone,ghrh)基因对梭鲈(Sander lucioperca)生长调控的作用,本研究利用RACE技术克隆获得了ghrh cDNA基因全长序列,并利用实时荧光定量PCR技术对其组织表达模式和大小个体间表达模式进行了分析。结果显示：ghrh基因cDNA全长为1 100 bp,包含494 bp的5′非编码区、180 bp的3′非编码区和编码141个氨基酸的开放阅读框。氨基酸多重比对发现,梭鲈ghrh与河鲈(Perca fluviatilis)、黄金鲈(P.flavescens)的ghrh氨基酸序列相似性分别为95.04%和94.33%,ghrh基因在鱼类和哺乳动物中都存在一个GLUCA保守结构域(65～91 aa)。ghrh基因在梭鲈各组织均有表达,脑组织中相对表达量最高,垂体次之,与其他组织相比差异显著。ghrh基因表达量与梭鲈体质量呈正相关,脑、肝和肌肉组织中ghrh基因表达量均为体质量极大组高于极小组,其中,脑组织中差异显著。因此,ghrh基因可以作为梭鲈生长候选基因用于分子选择育种。 相似文献
8.
coat-ε基因表达的蛋白是组成 COPⅠ的 coatomer 复合体的一个亚基,为获得中国明对虾(Fenneropenaeus chinensis) coat-ε基因全长序列,采用cDNA末端快速扩增(Rapid amplification of cDNA end, RACE)技术,扩增出coat-ε基因的3￠端和5￠端,测序结果经DNAMAN比对拼接得出coat-ε基因全长,基因全长1402 bp,5￠非编码区(UTR)84 bp,3￠非编码区(UTR)310 bp,开放阅读框1008 bp,预测编码335个氨基酸,其中,第230–300的氨基酸属于TPR超家族,SignalP 3.0 Server预测氨基酸序列没有信号肽,TMHMM Server v.2.0分析此氨基酸不存在跨膜结构,PSORTⅡ Prediction预测该蛋白位于线粒体、细胞质、内质网中,属胞内蛋白。系统进化树显示,中国明对虾的coat-ε基因与节肢动物门的动物亲缘关系相近。采用实时荧光定量方法分析该基因在鳃、上皮、胃、肌肉、肝胰腺等不同组织中的相对表达,结果显示,coat-ε在肌肉中的相对转录表达量最高,在鳃和附肢的表达次之。本研究获得的中国明对虾coat-ε全长序列,可为该基因功能研究提供基础。 相似文献
9.
肌肉生长抑制素(MSTN)是动物肌肉发育和生长过程中的负调控因子。为了明确淇河鲫MSTN基因序列及其在肌肉生长发育中的调控功能,本研究利用RACE方法克隆淇河鲫MSTN全长c DNA序列,q RT-PCR分析其在不同组织和胚胎发育阶段的表达情况。结果显示,淇河鲫MSTN c DNA序列全长2094 bp(no.KC851952.1),包含86 bp 5′非编码区、880 bp 3′非编码区和1128 bp开放阅读框,编码375个氨基酸残基,前22个氨基酸残基为信号肽,34~256位氨基酸残基为TGF-β前肽域,281~375是TGF-β结构域,具蛋白酶水解位点RIRR和C端生物活性区的9个保守半胱氨酸残基。蛋白同源分析发现淇河鲫MSTN与鲤形目鱼类相似性较高,与哺乳动物和鸟类的相似性最低。系统进化分析显示,淇河鲫MSTN与鲫、鲤、鳡等鲤科鱼类亲缘关系较近。实时定量PCR分析表明,淇河鲫MSTN基因在各个组织中均有表达,脑中表达量最高,其次为肌肉和肝脏,肠道表达量最低。淇河鲫胚胎发育的各阶段MSTN基因均有表达,受精卵表达量最高,其次为囊胚期,神经胚期表达量最低。推测MSTN与淇河鲫肌肉发育生长具有一定的相关性,可能参与"双背鲫"特征的形成。 相似文献
10.
奥利亚罗非鱼雌激素β受体两种亚型cDNA的克隆、组织分布及雌激素对其表达的影响 总被引：1，自引：1，他引：0
采用RT-PCR和RACE技术,克隆了奥利亚罗非鱼β雌激素受体基因(estrogen receptorβ,ERβ)两种亚型的cDNA全序列(ERβ1和ERβ2)。荧光定量PCR分析雌雄奥利亚罗非鱼两种亚型的组织分布,并观察注射外源雌激素对雄性奥利亚罗非鱼下丘脑-垂体-性腺轴雌激素受体ERα和β(β1/β2)基因表达的影响。序列分析表明,ERβ1cDNA全长为4262bp,其中包含239bp5′非编码区,2349bp3′非编码区和1674bp的开放阅读框,共编码557个氨基酸。ERβ2 cDNA全长为2506bp,包含5′非编码区393bp,3′非编码区109bp,阅读框为2004bp,共编码667个氨基酸。氨基酸序列同源性分析显示奥利亚罗非鱼ERβ1与尼罗罗非鱼的相似性高达99.1%,而与鲈形目其它鱼类的相似性为82.6%～94.2%。ERβ2氨基酸序列与尼罗罗非鱼的相似性为98.7%,与大口黑鲈、虹鳟、底鳉及斑马鱼的相似性分别为81.8%、76.3%、64.7%和55.0%。在系统进化树上奥利亚罗非鱼的ERβ1和ERβ2分别与尼罗罗非鱼的相应受体聚类。奥利亚罗非鱼ERβ1/β2基因在所检测的10种组织中均有... 相似文献
11.
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
12.
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
15.
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
17.
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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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
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Sandra García‐Garrido Ismael Hachero‐Cruzado Carlos Rosas Pedro Domingues 《Aquaculture Research》2013,44(11):1741-1751
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
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There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献