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报道了１２种药物在试管内对８株从患病白鲢上分离的嗜水气单胞菌的最小抑制浓度和最小杀菌浓度。被检测的８株致病菌对青霉素、氯霉素、甲哌利福霉素、土霉素有高度感受性，其最小抑菌浓度为０．０２５－１．５６μｇ／ｍｌ，最小杀菌浓度为０．０２５－３．１３μｇ／ｍｌ，最小抑菌和杀菌浓度比率为１－２。对红霉素、异烟肼、胜利霉素和呋喃唑酮的感受性较低，最小抑菌浓度为３．１３－２５μｇ／ｍｌ，最小杀菌浓度为６．２５－１００μｇ／ｍｌ，最小抑菌和杀菌浓度的比率为２－３。对磺胺胍、磺胺嘧啶、大蒜素和鱼健灵的感受性最低，最小抑菌浓度２５－＞１００μｇ／ｍｌ，最小杀菌浓度５０－＞１００μｇ／ｍｌ，其最小抑菌和杀菌浓度比率为１－＞２。 相似文献
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反相高效液相色谱法测维生素A含量 总被引：1，自引：0，他引：1
目的：建立一种用反相高效波相色谱测定维生素Ａ的方法。方法：色谱柱：Ｈｙｐｅｒｓｉｌ ＯＤＳ（１５０ｍｉｎ×４６ｍｍ）,流动相：甲醇－水（９６：４）,流速１．０ｍｌ／ｍｉｎ,紫外检测器波长３２５ｎｍ,柱温２５℃,外标法测定。结果：维生素 Ａ在 ２．５～３０．０μｇ／ｍｌ之间有良好的线性关系,最低检测浓度为 １．５μｇ／ｍｌ,平均回收率为９８．５％,精密度ＲＳＤ±ｌ、５６％（ｎ＝３）。结论：本方法准确、灵敏、适应面广。 相似文献
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报道了１２例药物在试管内对８株从患病白链上分离的嗜水气单胞菌的最小抑制浓度和最小杀菌浓度。被检测的８株致病菌对青霉素、氯霉素、甲哌利福霉素、土霉素有高度感受性，其最小抑菌浓度为０．０２５－１．５６μｇ／ｍｌ，最小杀菌浓度为０．０２５－３．１３μｇ／ｍｌ，最小抑菌和杀菌浓度比率为１－２。对红霉素、异烟肼、胜利霉素和呋喃唑酮的感受性较低，最小抑菌浓度为３．１３－２５μｇ／ｍｌ，最小杀菌浓度为６．２５－ 相似文献
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胡子鲶血浆中外源生长激素的代谢动力学 总被引：5，自引：0，他引：5
采用草鱼生长激素夹心式酶联免疫吸附测定法（ＥＬＩＳＡ）研究了重组鲤生长激素（ｒｃＧＨ）在胡子鲶血浆中的代谢动力学,肌肉注射ｒｃＧＨ（０．２和１μｇ／ｇ）后,胡子鲶血浆ｒｃＧＨ水平迅速升高,于２和３ｈ时达峰值,随后下降,在注射后第２和４天,血浆中检测不到ｒｃＧＨ,腹腔注射ｒｃＧＨ（０．２和１μｇ／ｇ）后,胡子鲶血浆ｒｃＧＨ水平也有同上类似的变动规律,胡子鲶腹腔注射０．５,１和２μｇ／ｇ的ｒｃＧＨ７天 相似文献
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实验结果表明，ＬＨＲＨ－Ａ诱导泥鳅排卵的最佳剂量为０．１μｇ／ｇ体重；利血平４μｇ＋ＬＨＲＨ－Ａ０．１μＧ／Ｇ体重与多巴胺４μｇ＋ＬＨＲＨ－Ａ０．１μｇ／ｇ理为最佳剂量。 相似文献
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乳山湾海水,底质及贝类体内砷的研究 总被引：6，自引：0，他引：6
通过１９９５年６－９月对乳山湾的综合调查，初步摸清了乳山湾海水，底质及贝类体内砷的分布。该水域内砷的浓度范围为０．７２－６．８０μｇ／Ｌ，其平均值为１．９４μｇ／Ｌ；底质中砷的含量范围为５．０－９．６ｍｇ／ｋｇ，平均值为７．７７ｍｇ／ｋｇ； 相似文献
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氯化物水型盐碱池塘的限制性营养盐研究↑（*） 总被引：9，自引：0，他引：9
研究了沿黄盐碱地池塘水（ＣｌⅡＮａ 和ＣｌⅢＮａ） 的主要营养盐（Ｎ、Ｐ） 的限制作用和适宜施肥浓度。首次发现该类型池塘普遍表现为氮限制。塘水中无机氮浓度很低,只有（２３ ．５６ ±１２ ．５３） μｇ／Ｌ（ Ｍ±ＳＤ） ,与无机磷的比值仅为１ ．０２ ±０ ．８５ ;而总氮和总磷并不低,分别为（３ ．３５ ±１ ．０８） ｍｇ／Ｌ 和（０ ．２４ ±０ ．１１） ｍｇ／Ｌ;ＴＮ／ＴＰ为１４ ．９４ ±３ ．４３ 。适宜的施肥Ｎ∶Ｐ（ 重量） 为（１０ ～１５）∶１ 。文中提出了１ 种氮限制指数：ＩＮＬ＝ （ＤＯＩＮ１ ．０－ ＤＯＩｃ）／（ＤＯＩＮ１ ．０Ｐ０ ．１ － ＤＯＩｃ） ,并拟合出ＩＮＬ 与ＴＮ／ＴＰ的相关模型,ＩＮＬ 可准确地表示氮限制程度。文章最后分析了氮限制的原因。 相似文献
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对虾池封闭式三元综合养殖的实验研究↑（*） 总被引：5，自引：0，他引：5
采用海水陆基围隔实验法探讨以对虾为主的中国对虾（ Ｐｅｎａｅｕｓ ｃｈｉｎｅｎｓｉｓ） 、罗非鱼（ Ｏ．ｍｏｓｓａｂｉｃｕｓ×Ｏ．ｎｉｌｏｔｉｃｕｓ） 和缢蛏（ Ｓｉｎｏｎｏｖａｃｕｌａ ｃｏｎｓｔｒｉｃｔａ） 投饵混养的最佳结构及Ｎ、Ｐ 的利用率等,并比较其养殖效果。结果表明,对虾的成活率、规格和净产量分别为７０ ．７４ ～８１ ．９５ ％ 、９ ．１６ ～１０ ．２１ ｇ／ｉｎｄ 和４８５ ．４ ～５６７ ．６ｋｇ／ｈｍ２ ;罗非鱼的出塘规格和净产量为２０２ ．４ ～２４２ ．５ ｇ／ｉｎｄ 和６６ ．９ ～１９１ ．９ ｋｇ／ｈｍ２ ;缢蛏的出塘规格和净产量分别为５ ．２３ ～６ ．１２ ｇ／ｉｎｄ 和１４０ ．４ ～４５６ ．５ ｋｇ／ｈｍ２ 。最佳结构与放养个体数的配比为对虾７ ．２１ ｉｎｄ／ｍ２（ 体长２ ｃｍ 左右） 、罗非鱼（ 体重１５０ ｇ 左右）０ ．０８ ｉｎｄ／ｍ ２ 和缢蛏（ 壳长３ ｃｍ 左右）１４ ｉｎｄ／ｍ２ 组,其Ｎ、Ｐ的总利用率为２３ ．３９ ％ 和１４ ．６６ ％ 。 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
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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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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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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