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1.
低温对菲律宾蛤仔能量收支的影响 总被引：6，自引：0，他引：6
在实验室内采用静水法，测定了在315和8℃下，菲律宾蛤仔的耗氧率和排氨率与体重的关系及其能量收支情况。实验数据显示，在实验的温度范围内，菲律宾蛤仔的耗氧率和排氨率都与体重负相关；温度对耗氧率的影响与体重有关。摄食率、生长率（净生长率、毛生长率）与温度正相关。温度对能量分配影响较大，代谢分配率、排粪分配率随温度的升高而降低，且变化极其显著（P＜0.01)；生长分配率随温度的升高而增大。在能量收支方程中，排粪能所占比例较大，在41.131%-60.69%之间，代谢能在23.37%－32.73%之间，生长能在6.13%-34.63%之间，排泄能所占的比例最小，低于3％。 相似文献
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菲律宾蛤 仔生理生态学研究：Ⅱ.温度,饵料对同化率的影响 总被引：4，自引：0，他引：4
在室内试验条件下,研究了温度、饵料的种类、密度和质量对菲律宾蛤仔同化率的影响。试验结果显示,随水温的升高,菲律宾蛤仔滤水率、摄食率、同化率以及净生长率均有明显的增加,经方差分析（ＡＮＯＶＡ）显示,温度对它们的影响极显著。菲律宾蛤仔对新月菱形藻、球等鞭金藻和亚心形扁藻的同化率基本相同。饵料的丰度和质量是影响菲律宾蛤仔同化率的重要因素,随食物中有机物含量（ＰＯＭ/ＴＰＭ）的增加,同化率也增加;且随饵料 相似文献
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试验采用室内静水法,测定了低温条件下(5～10℃)的菲律宾蛤仔(Ruditapes philippinarum)(软体部分平均干重为0.91±0.06 g)对蛋白核小球藻(Chlorella pyrenoidosa)的摄食率(IR)和同化率(AE),其中蛋白核小球藻的浓度为(5.7±0.3)×104cells/mL。结果显示,菲律宾蛤仔对小球藻的摄食率和同化率均随温度的升高而增加,在试验温度范围内,各组之间菲律宾蛤仔的摄食率有显著性差异(P<0.05);同化率为42.95%～51.10%,差异不显著(P>0.05)。结果表明菲律宾蛤仔在低温下仍能生存。 相似文献
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菲律宾蛤仔生理生态学研究 Ⅰ.温度、体重及摄食状态对耗氧率及排氨率的影响 总被引：8，自引：0，他引：8
在室内试验条件下研究了温度、体重及摄食状态对菲律宾蛤仔的耗氧率和排氨率的影响。结果显示,菲律宾蛤仔的耗氧率和排氨率与体重呈负相关关系,而与温度呈正相关关系,并符合下列模式, Ｑｏ ＝ ２ ．０１５ Ｗ－ ０ ．６３５（ Ｒ ＝ － ０．９６９, Ｐ ＜ ０ ．０１ ,ｎ ＝ １４） 和Ｑｎ ＝ ０ ．０６９ Ｗ－０ ．３６９（ Ｒ ＝ ０．７５４ ,Ｐ＜ ０ ．０１ ,ｎ ＝ １３）。在摄食状态下,菲律宾蛤仔的耗氧率和排氨率比饥饿状态有大幅度的提高,分别提高了７５ ．３ ％ 和４０３ ．７ ％ ,表明在摄食状态下蛋白质的代谢明显增加 相似文献
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菲律宾蛤仔生理生态学研究：Ⅰ.温度,体重及摄食状态对耗氧率及排？… 总被引：3，自引：0，他引：3
在室内试验条件下研究了温度、体重及摄食状态对菲律宾蛤仔的耗氧率和排氨率的影响。结果显示,菲律宾蛤仔的耗氧率和排氨率与体重呈负相关关系,而与温度呈正相关关系,并符合下列模式,Ｑｏ＝２．０１５Ｗ＾－０．６３５（ｒ＝－０．９６９,ｐ〈０．０１,Ｎ＝１４）和Ｑｎ＝０．０６９Ｗ＾－０．３６９（Ｒ＝０．７５４,Ｐ〈０．０１,ｎ＝１３）。在摄食状态下,菲律宾蛤仔的耗氧率和排氨率比饥饿状态有大幅度的提高,分别提高 相似文献
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以等边金藻3011为饵料,采用室内流水法,在12、20和24℃3个温度和不同的壳长、饵料浓度下,测定并计算了温度、壳长和饵料浓度与菲律宾蛤仔摄食率的关系,并建立了相关数学模型。结果显示,在实验条件范围内,摄食率随着饵料浓度的增大而增大,且符合幂函数方程。摄食率可以用温度、壳长和饵料浓度的自然对数方程表示,其模型为：IR=21．2LnT＋20．06LnL＋7．10LnC-97．95,经协方差分析结果表明,其相关系数呈非常显著水平。 相似文献
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为了解不同水温环境中(5~25℃)多棘海盘车(4~8 cm)对菲律宾蛤仔(20~40 mm)的摄食选择性,本实验利用饵料收益率、摄食规格选择性、摄食量与摄食率等指数,分析了温度、多棘海盘车规格及饵料规格对多棘海盘车摄食选择性的影响。结果显示,实验条件下,捕食者及被捕食者规格对饵料收益率影响显著,温度对饵料收益率影响不显著;根据饵料收益模型,4种规格多棘海盘车依次在摄食20、23、30和35 mm蛤仔时的饵料收益率最大,收益率分别为0.62、0.70、0.83、0.94 mg/min;5~15℃条件下,摄食量随水温升高而增大,15℃为多棘海盘车摄食蛤仔的最适水温,此时5~8 cm多棘海盘车摄食量均达最大值,分别为0.37、0.45和0.54 g/d,之后随水温升高摄食量减小;摄食率昼夜差异显著,夜间显著高于白天;青岛近海5—6月的水温(13~18℃)为蛤仔春季繁殖的适宜水温,也是多棘海盘车最适生长和摄食温度,此时应加强对多棘海盘车的防治和清除。 相似文献
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采用实验生态学方法,研究了魁蚶(Scapharca broughtonii)摄食、呼吸代谢及能量收支对短期酸化(pH分别为8.2、7.9、7.6)的响应。结果显示,魁蚶的摄食率(IR)和排粪率(FER)均受pH影响显著(P<0.05),都随pH的降低而减少;魁蚶的耗氧率(OR)受pH影响显著(P<0.05),随pH降低呈明显的下降趋势,表明低pH在一定程度上抑制魁蚶的呼吸;排氨率(NR)受pH影响不显著,随pH的降低呈先下降再上升的趋势;O : N值随pH的降低而减小。不同pH条件下的能量收支结果显示,魁蚶的摄食能、呼吸能、排粪能和生长余力(SFG)均随pH的降低而减少。通过建立能量收支方程发现,pH显著影响魁蚶的能量分配(P<0.05),随pH的降低,魁蚶的呼吸能和排泄能占摄食能的比例增加,而排粪能和生长能占比减少,说明低pH条件下,魁蚶会做出适当生理调整降低IR,增加代谢率,导致能量减少,继而造成SFG减少。研究表明,短期酸化条件下,魁蚶的摄食和新陈代谢显著降低,可能是细胞能量需求的增加和氮损失的协同作用。 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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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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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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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