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1.
用放在海水池塘中的８个陆基围隔（５０ｍ×５０ｍ×１８ｍ），研究中国对虾（Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ）与不同密度海湾扇贝（Ａｒｇｏｐｅｃｔｅｎｉｒａｄｉａｎｓ）投饵混养的放养方式、生产力和极限放养量。对虾体长（２８５±０１６）ｃｍ，扇贝壳长（１１０±０１２）ｃｍ，放养密度分别为６０尾／ｍ２和０，１５，４５，７５粒／ｍ２，用投饵和施肥（鸡粪和化肥）饲养。结果表明，扇贝密度为０和１５粒／ｍ２时，对虾的成活率无显著差异。混养（扇贝１５粒／ｍ２）时对虾的出塘体长、体重和产量分别比单养高２５％，３８％和６５％；当扇贝密度高于１５粒／ｍ２时，对虾的平均体长、体重和产量随扇贝密度的增加而显著减少（Ｐ＜００５）。扇贝密度为１５和７５粒／ｍ２时，其产量由４７０ｋｇ／ｈｍ２增至１２３６ｋｇ／ｈｍ２；当扇贝密度高时，去壳后湿重占体重的百分数从（４２８４±３４４）％降至（３７８８±４２６）％。扇贝的极限放养量为６００～８００ｋｇ／ｈｍ２，适宜放养密度为１０～１５粒／ｍ２。 相似文献
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１９９４年７月，进行了太平洋牡蛎常温育苗，８月１８日将１亿粒蛎苗转入虾池保苗。越冬后，出售３ｃｍ左右的商品苗６８５０万粒，保苗率６８．５％，每亩纯益２．２万元，投入产出比１：１５．２。 相似文献
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在实验条件下，研究了斯必兰（Ｇｙｍｎｏｃｏｒｏｖｉｓｓｐｉｌａｎｔｈｏｉｄｅｓ）、羽毛草（Ｍｙｒｉｏｐｈｙｌｌｕｍａｑｕａｔｉｃｍ）和水芹（Ｏｅｎａｎｔｈｅ
ｊａｖａｎｉｃａ）３种观赏水草对不同浓度的镉污染水体（Ｃｄ２＋ ０．５、１．０、５．０、１０．０ｍｇ／Ｌ）的修复效果以及镉对这３种观赏水草生长的影响。研究结果表明：３种观赏水草均对水体镉污染有一定程度的抗性并能不同程度地去除水体中的镉，其抗性和去除效率的大小均表现为斯必兰＞水芹＞羽毛草；３种观赏水草对镉的富集能力也为斯必兰＞水芹＞羽毛草。以上实验结果表明，在３种观赏水草中斯必兰对水体镉污染的耐性最高、修复能力最强。 相似文献
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１９９２年，在５０ｍ＾３水体中，太平洋牡蛎控温育苗量为２０．２万粒／ｍ＾３。当年筏式殖６个月，亩产５６７０ｋｇ，利税６４００元平均亮高８ｃｍ以上，个体重９７．４ｇ，比常温育苗，可缩短养殖周期近１年，专家鉴定认为：本研究属国内首创，居国内领先水平。 相似文献
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为了得到壳型规则、大小均一的单体牡蛎,本研究采用肾上腺素对岩牡蛎单体苗种生产的诱导条件进行研究,阐明了岩牡蛎单体苗种的最适诱导浓度、诱导时间和诱导密度。结果显示,肾上腺素能显著诱导岩牡蛎幼虫的不固着变态,最适诱导浓度为5×10–5 mol/L,最适诱导时间为1 h,提高诱导浓度和延长诱导时间导致岩牡蛎幼虫的不固着变态率、稚贝壳高和存活率显著降低;肾上腺素对低于8个/mL幼虫密度的诱导效果差异不显著,但稚贝壳高和存活率在8个/mL的培育密度下显著低于0.5～4个/mL,研究表明利用肾上腺素诱导岩牡蛎单体时,可大批量处理眼点幼虫,但稚贝充气培养的最适培养密度应不高于4个/mL。 相似文献
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采用自育自繁亲虾，用温泉水高温，人工育苗１８．５９万尾（０．８－１．０ｃｍ），最高育苗密度１０．３万尾／ｍ＾３，成活率８４．５％；外购亲虾用锅炉提温，人工育苗７．７９万尾（１．６５ｃｍ），育苗密度５．５３万尾／ｍ＾３，成活率６４．９８％，孵化育苗水温２６．０－３０．０℃、ＰＨ７－８．５、盐度１２－１４‰、溶氟４－６．５ｍｇ／ｌ，氨氮０．３－０．８ｍｇ／ｌ。本试验表明，罗氏沼虾人工孵化育苗，在辽宁地 相似文献
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中国对虾与罗非鱼施肥混养的基础研究↑（*） 总被引：3，自引：0，他引：3
用４个海水池塘陆基围隔（５ｍ×５ｍ）,进行了封闭式施肥混养中国对虾（Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ）与台湾红罗非鱼（Ｏｒｅｏｃｈｒｏｍｉｓｍｏｓａｍｂｉｃｕｓ×Ｏ．ｎｉｌｏｔｉｃｕｓ）的基础研究。结果表明,在不同密度条件下,对虾成活率４５．０％～８６．７％（平均６６４．２％）,产量为７５．７～１１１．８ｋｇ／ｈｍ２（５７ｄ）,生产力为０．１９／ｍ２·ｄ。池塘对中国对虾的负荷力为１７０．０ｋｇ／ｈｍ２。其中某些围隔对虾死亡较多的原因是负荷量超过了负荷力,发生饵料缺乏和自残。在限定罗非鱼放养量（８×１０３尾／ｈｍ２）的条件下,鱼虾最适放养尾数配比为１∶３,中国对虾（体长５．５５ｃｍ）的最适放养量为２４×１０３尾／ｈｍ２左右。 相似文献
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烟台浅海区不同养殖系统养殖效果的比较 总被引：11，自引：1，他引：10
于１９９８年４月５日至６月２３日,在山东烟台市四十里湾海区进行了３种养殖模式养殖效果比较的模拟实验。在该海区岸边建立了栉孔扇贝（Ｃｈａｍｙｓ ｆａｒｒｅｒｉ）单养,栉孔扇贝和海带（Ｌａｍｉｎａｒｉａ ｊａｐｏｎｉｃａ）混养,栉孔扇贝、海带和刺参（Ａｐｏｓｔｉｃｈｏｐｕｓ ｊａｐｏｎｉｃｕｓ）混养等３个系列、９个养殖系统和１个对照系统（５．０ｍ＊２．０ｍ＊１．０ｍ,日换水量１００％）,进行对比实验。 相似文献
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虾夷马粪海胆１９８９年５月从日本北海道引入大连，初引进海胆壳径为０．５～１．３ｃｍ，养至１９９０年１０月性成熟并进行首次育苗，培育出Ｆ１代，其后１９９３年～１９９５年又培育出Ｆ２和Ｆ３代约５００万枚。亲海胆采取海区笼养和室内促熟方法。诱产用阴干与流水、注射０．５ＭＫＣｌ、加入性产物三种催产方法可成功获得成熟精、卵。受精卵孵化需１１．５～１２．５ｈ（１６．０～１８．５℃）达囊胚期上浮，后经二腕、四腕、六腕、八腕幼虫，以纤细角刺藻为饵料，１８～２１天（１５．０～１８．５℃）变态附着为稚海胆并摄食底栖硅藻，３０天～５０天达０．２～０．３ｃｍ以上剥离投喂石莼、囊藻、海带等，当壳径长至０．５～１．０ｃｍ以上时可下海养殖。 相似文献
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１．购买苗种要求：规格０．８－１．０ｃｍ，经过初步淡化，须淡化至１．００５（即７．５‰）即可。 ２．暂养池要求：在池塘的一角围出若干平方米的暂养池（用彩条布围拦），暂养池面积大小按１０００尾／ｍ２设计，暂养池的水深须在０．５ｍ以上，并在暂养池内安装气头，须连续进行供气，同时将暂养池的盐度调到５‰（即每立方水体投入５ｋｇ盐巴），事先将水质进行消毒（采用二溴海因０．２－０．３ｐｐｍ泼洒）、肥水（用生物肥水精培藻，每亩投放４ｋｇ，使水色呈茶褐色），并将ｐＨ调整到８．０以上（可采用生石灰）。 ３．放苗后的… 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
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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
16.
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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Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献
20.
William King V David L. Berlinsky Craig V. Sullivan 《Fish physiology and biochemistry》1995,14(6):489-500
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass. 相似文献