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28株水产动物致病菌的编码鉴定 总被引：10，自引：0，他引：10
采用国产革兰氏阴性杆菌编码鉴定系列培养基对28株细菌进行鉴定。结果显示：除2株细菌未能得到鉴定外，其余26株细菌均鉴定到属或种水平，可鉴定率为92．86％．但各菌株的鉴定概率和模式频率有所不同。26株可鉴定菌分布于气单胞菌属(Aeromonas)、假单胞菌属(Pseudomonas)、不动杆菌属(Acinetobacter)、摩根氏菌属(Morganella)、弧菌属(Vibrio)、变形杆菌属(Proteus)、黄单胞菌属(Xanthomonas)、邻单胞菌属(Plesiomonas)和埃希氏菌属(Escherichia)9个菌属，其中13株为气单胞菌(Aeromonas)；3株为恶臭假单胞菌(P．putide)；2株为摩氏摩根氏菌(M.morganella)；2株为不动杆菌(Acinetobacter)；2株为类志贺邻单胞菌(P．shigelloides)；拟态弧菌(V．mimicus)、普通变形杆菌(P．vulgaris)、嗜麦芽黄单胞菌(X．maltophilia)和大肠埃希氏菌(E．coli)各l株。基本上摸清了安徽省水产养殖动物常见病原菌的种类。 相似文献
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2009年4月—2010年10月对河北省白洋淀营外寄生生活的车轮虫属进行种类鉴定工作。采用干银染色法显示车轮虫的附着盘结构,活体吉姆萨染色方法显示细胞核形态。采用"统一特定方法"和"齿体定位描述法"鉴定出车轮虫属9种,分别为显著车轮虫、拟黑色车轮虫、网状车轮虫、杜氏车轮虫、异齿车轮虫、喙状车轮虫、卡氏车轮虫、短棘车轮虫、适度车轮虫。波氏吻鱼叚虎鱼为显著车轮虫、拟黑色车轮虫、网状车轮虫的新宿主记录,黄黝鱼为异齿车轮虫和杜氏车轮虫的新宿主记录,麦穗鱼为喙状车轮虫的新宿主记录,鲫鱼和圆尾斗鱼为适度车轮虫的新宿主记录。该研究是白洋淀地区乃至华北地区车轮虫属首次细致的分类描述,研究结果将有助于阐明白洋淀鱼类寄生车轮虫区系组成。 相似文献
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氯虫苯甲酰胺对克氏原螯虾的急性毒性试验 总被引：1，自引：0，他引：1
为探索并评价新型农药——氯虫苯甲酰胺对克氏原螯虾(Procambarus clarkii)的安全特性,在水温(29±2)℃、p H 8.0±0.2、溶氧量(5.1±0.9)mg/L条件下,采用静水式方法,开展了氯虫苯甲酰胺对克氏原螯虾的急性毒性试验。结果显示:氯虫苯甲酰胺对克氏原螯虾的24、48、96 h半致死浓度分别为795.93、563.47、335.64 mg/L;氯虫苯甲酰胺对克氏原螯虾的安全浓度为84.72 mg/L。跟据《化学农药环境安全评价试验准则》,氯虫苯甲酰胺属低毒级农药,对克氏原螯虾的毒副作用较小,可在克氏原螯虾养殖生产中安全使用。 相似文献
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长江中游长吻(鱼危)幼体长江丽棘虫感染率高达84.5%,感染强度为16.4(1～48).1龄长吻(鱼危)感染率96.3%,感染强度17.1;2龄鱼为76.6%、15.6;3龄鱼体内未检出长江丽棘虫.80%长江丽棘虫集丛分布在长吻(鱼危)危小肠的前段,雌体明显多于雄体.长江丽棘虫在长吻鱼危幼体种群中的分布为聚集分布型式. 相似文献
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在常温静水条件下,探讨了鱼虫清对欧洲鳗（Anguilla angulla）的急性毒性效应,同时进行了鱼虫清对寄生虫的杀灭试验。结果表明：鱼虫清对欧洲鳗的24h、48h、96h的半致死浓度（LC50）分别为1.87mg/L、1.67mg/L和1.35mg/L,安全浓度为0.4mg/L。鱼虫清对指环虫（Dactylogyrus）和车轮虫（Trichodinella）的杀灭效果分别为：浓度在0.30mg/L、0.20mg/L以上作用24h,杀虫率可达100%。试验证明,鱼虫清对杀灭指环虫和车轮虫有很好的效果,值得推广。 相似文献
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长江中游长吻鱼危幼体长江丽棘虫感染率高达 84 5 % ,感染强度为 1 6 4 (1～ 48)。 1龄长吻鱼危感染率 96 3% ,感染强度 1 7 1 ;2龄鱼为 76 6 %、1 5 6 ;3龄鱼体内未检出长江丽棘虫。 80 %长江丽棘虫集丛分布在长吻鱼危小肠的前段 ,雌体明显多于雄体。长江丽棘虫在长吻鱼危幼体种群中的分布为聚集分布型式 相似文献
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锚头鳋是我国水产养殖业中常见的、对鱼(蛙)类危害较大的寄生虫,渔农常称之为“铁锚虫”、“针虫”、“蓑衣虫”等,对它的治疗,化学药物一般采用高锰酸钾、敌百虫、鱼虫净、鱼虫清等,但往往很难根治,需多次用药,还易产生药物中毒、环境污染和耐药性等公害。怎样才能有效治疗该病而又无公害呢?综合国内外防治成果,结合笔者诊治经验,建议采用下述非化学药物治疗法,并请广大渔农不妨选择一用。 责任编辑 刘学迅鱼病诊治1.根据虫体的不同发育阶段,可将成虫分为“童虫”、“壮虫”、“老虫”三种形态,如果多为“老虫”,则可以… 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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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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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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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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