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栉孔扇贝能量收支的研究 总被引：5，自引：0，他引：5
报道了在模拟自然条件下栉孔扇贝能量收支研究的实验结果。实验数据显示,在实验的温度范围内（８～１７．２℃）栉孔扇 贝的个体耗氧率和个体排氨率随壳长的增大和水浊的升高而增大,呈下相关关系。栉孔扇贝的个体大小是影响能量收支各组分比例的主要因素。随个体的增大,扇贝的呼吸能增大,而生长能减小。在能量收支方程中,呼吸能占的比例最大（４４．２％～５１．７）,其次是排粪能（３１．４％～３６．８％）,第三为生长能（ 相似文献
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不同生长时期中国对虾蛋白酶,脂肪酶活性变化的研究 总被引：1，自引：0，他引：1
本文对中国对虾生长各阶段的蛋白酶和脂肪酶活性变化进行了分析，探讨了蛋白质和脂肪的消化利用。结果表明，从中国对虾生长与消化酶活性的关系可将其分为两个生长阶段。第一阶段，体长在２．５５－１０．１１ｃｍ间（饲养时间为６月８日至８月２７日），在这一时期随着个体增大蛋白酶，脂肪酶活性不断升高。９月份对虾消化酶活性趋于下降，构成了在养殖后期消化功能趋于减弱的第二阶段。进入繁殖期的对虾与个体大小相似的生长期对虾 相似文献
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不同温度下太平洋牡蛎三倍体和二倍体生物能量学比较 总被引：5，自引：0，他引：5
对一龄太平洋牡蛎三倍体和二倍体能量收支比较研究的结果表明,在５～３０℃下,二倍体摄入能量的３２％为粪能、３．６５％为排泄能、４１．６６％消耗于呼吸、２２．８１％用于生物生长;三倍体摄入能量的２３％为粪能、７．５４％为排泄能、４０．６５％的能量用于呼吸、２８．７８％为生长。经协方差检验,倍性和温度对牡蛎的生长能、同化能和排泄能影响显著,对代谢能和摄食能作用不明显。实验还表明,二倍体Ｋ２值平均３３．９ 相似文献
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不同生长时期中国对虾蛋白酶、脂肪酶活性变化的研究 总被引：12，自引：1，他引：12
本文对中国对虾生长各阶段的蛋白酶和脂肪酶活性变化进行了分析，探讨了蛋白质和脂肪的消化利用。结果表明，从中国对虾生长与消化酶活性的关系可将其分为两个生长阶段。第一阶段，体长在２．５５─１０．１１ｃｍ间（饲养时间为６月８日至８月２７日），在这一时期随着个体增大蛋白酶，脂肪酶活性不断升高。９月份对虾消化酶活性趋于下降，构成了在养殖后期消化功能趋于减弱的第二阶段。进入繁殖期的对虾与个体大小相似的生长期对虾相比较，不同组织的蛋白酶和脂肪酶活性差别情况不同，但总趋势是性腺发育的对虾蛋白酶、脂肪酶活性强于生长期对虾，海捕越冬亲虾蛋白酶、脂肪酶活性高于人工养殖越冬亲虾。 相似文献
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以亚心形扁藻为饵料,分别研究了盐度（15、20、25、30、35％o）、温度（10、15、20、25、30℃）对能量收支的影响。测定了马氏珠母贝的摄食能、生长能、呼吸能、排泄能、排粪能以及各组分占摄食能的比例。结果表明：（1）盐度梯度下,马氏珠母贝摄食能、生长能、呼吸能、排泄能及排粪能均有显著性差异（P〈o．05）;从占摄食能比例看出,盐度为30％。时的生长能、呼吸能、排泄能与其余梯度间存在显著性差异（P〈0．05）;（2）温度梯度下,贝的摄食能、生长能、呼吸能及排泄能与其他4个饵料浓度下的差异显著（P〈0．05）;从占摄食能的比例看出,温度为25℃时,生长能、排粪能与其余4温度组差异性显著（P〈O．05）。 相似文献
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对虾池不同综合养殖系统效率和效益的比较研究 总被引：7，自引：0，他引：7
利用５０个５．０×５．０×１．８ｍ陆基围隔研究了中国对虾与台湾红罗非鱼、海湾扇贝和缢蛏投饵或施肥混养及鲈鱼与中国对虾和台湾红罗非鱼混养最佳结构的生态效率、生产效果和经济效益。结果表明,几种综合养殖系统最佳结构下各种养殖对象对Ｎ的绝对利用率由高至低依次为：鲈鱼－对虾－罗非鱼（３０．９１％）＞对虾－海湾扇贝（２１．０９％）＞对虾－罗非鱼施肥混养（２０．１２％）＞对虾－罗非鱼投饵混养（１７．８１％）＞对虾－缢蛏（１６．９３％）＞单养对虾（１１．５２％）;对Ｐ的绝对利用率由高至低依次为：对虾－缢蛏（１６．０８％）＞鲈鱼－对虾－罗非鱼（１２．８３％）＞对虾－罗非鱼投饵混养（１２．６３％）＞单养对虾（１０．８８％）＞对虾－海湾扇贝（６．０１％）＞对虾－罗非鱼施肥混养（４．０４％）;其产出投入比由高至低依次为：对虾－罗非鱼投饵混养（１．９９）＞对虾－罗非鱼施肥混养（１．９８）＞对虾－海湾扇贝（１．５３）＞单养对虾（１．３８）＞鲈鱼－对虾－罗非鱼（１．３０）＞对虾－缢蛏（１．２３）。 相似文献
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在室内流水条件下测定不同温度（１５℃、２０℃、２５℃和３０℃）对长吻幼鱼摄食，生长及饲料转化效率的影响。结果表明：长吻摄食与生长的起始温度为１５℃；适宜温度区为２０—３０℃；最适温度为２５℃左右。水温为１０℃时，长吻 基本不摄食，水温为１５—２５℃时，长吻摄食率、生长率随永温升高而显著增加，２５℃和３０℃组间差异不大。饲料转化效率随水温上升明显提高，但水温升至３０℃时，饲料转化效率有下降的趋势。长吻幼鱼日投饵量可根据经验公式：Ｃ＝０．１４８Ｔ￣（１．６２６）Ｗ￣（－０．５２１）计算。 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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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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