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1.
以水体甲基汞不同浓度（μｇ／Ｌ）分别染毒鲤鱼２４小时和１周。实验结果表明：在浓度高于５０μｇ／Ｌ染毒２４小时和浓度２０μｇ／Ｌ染毒１周时，多数染毒鱼的血浆Ｋ＋和Ｍｇ２＋浓度增高，Ｎａ＋和Ｃｌ－浓度下降，ＰＯ３－４值变化不明显。血浆Ｃａ２＋浓度仅在２００μｇ／Ｌ染毒２４小时和高于４０μｇ／Ｌ染毒１周时，染毒鱼的血浆Ｃａ２＋出现极显著下降。甲基汞量高于１００μｇ／Ｌ染毒２４小时和８０μｇ／Ｌ染毒１周，染毒鱼的血浆渗透压呈明显下降趋势。鳃线粒体Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性仅在染毒２４小时浓度为２５μｇ／Ｌ和５０μｇ／Ｌ剂量时受到抑制。甲基汞还引起了血糖含量的明显增高。 相似文献
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暗纹东方鲀生殖洄游期性腺发育特点及人工繁殖的研究 总被引：3，自引：1，他引：2
１９９６～１９９８年,作者从长江下游扬中段采捕暗纹东方鱼屯亲鱼,经暂养促熟处理（微流水刺激、投喂鲜活饵料、不定期注射适量的ＬＨＲＨ－Ａ２）,雌鱼的性腺可发育到Ⅳ期末,对外源激素能引起正常的排卵反应。同时观察了Ⅲ、Ⅳ、Ⅴ期性腺发育的特点。催产药物为ＬＨＲＨ－Ａ２和ＰＧ,三针注射,雌鱼剂量为３５ｍｇＰＧ＋６０μｇＬＨＲＨ－Ａ２／ｋｇ,雄鱼剂量减半。在水温１８～２２℃的条件下,效应时间为１０～３６小时;在２１～２２℃时,胚胎发育时间为１３９～２１０小时。１９９７～１９９８年的平均受精率为８３４％,平均孵化率为７８０％。 相似文献
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暗纹东方Tun生殖洄游期性腺发育特点及人工繁殖的研究 总被引：2，自引：0，他引：2
１９９６￣１９９８年,作者从长江下游扬中段采捕暗纹东方Ｔｕｎ亲鱼,经暂养促熟处理（微流水刺激、投喂鲜活饵料、不定期注射适量的ＬＨＲＨ－Ａ２）,雌鱼的性腺可发育到ＩＶ期末,对外源激素能引起正常的排卵反应。同时观察了Ⅲ、Ⅳ、Ⅴ期性腺发育的特点。催产药物为ＬＨＲＨ－Ａ２和ＰＧ,三针注射,雌鱼剂量为３．５ｍｇＰＧ＋６０μｇＬＨＲＨ－Ａ２／ｋｇ,雄鱼剂量减半。在水温１８￣２２℃的条件下,效应时间为１０￣３６ 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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微量元素在盐碱地新池塘配方施肥培育鱼种中的效果研究 总被引：1，自引：0，他引：1
在施足基肥的盐碱地新池塘中,将有机肥、无机肥氮、磷、微量元素按比例连续不断地配方施肥和水质调控,使水体中ＮＨ４＾＋－Ｎ＋ＮＨ３－Ｎ为０．８３５ ８ｍｇ／Ｌ,ＰＯ４＾３－－Ｐ为０．１２８ ６ｍｇ／Ｌ,ＳｉＯ２为１．４９ｍｇ／Ｌ,Ｎ／Ｐ为６．０２：１。微量元素Ｆｅ、Ｂ、Ｍｎ、Ｚｎ、Ｍｏ、Ｃｏ分别按６０、５０、５０、５、５、５μｇ／Ｌ施入池水,隐藻、硅藻为优势种群的浮游植物总生物量达到４６．９３９ｍｇ／ 相似文献
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本文报道网箱养殖杜氏Ｓｈｉ链球菌及其他常见病害的防治。链球菌病的防治：鱼种阶段在饲料中加入氨苄青霉素７．５ｇ／１０００尾／ｄ,每个疗程５－７ｄ,隔７－１０ｄ进行下一次疗程,使用４个疗程,９０ｄ内不发病;成鱼采用肌肉注射青霉素Ｇ,剂量为;体重４００－５００ｇ注射２０－４０万ＩＵ／尾,体重５００－１０００ｇ注射４０－８０万ＩＵ／尾、体重１０００ｇ以上注射８０万ＩＵ／尾１－３次,预防时１１０－１２０ｄ内 相似文献
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青岛近岸水域挥发性酚的分布及在贝类体内的积累 总被引：2，自引：0，他引：2
根据１９９８年４－１０月对青岛市近岸水域及贝类养殖区的综合调查结果,初步摸清了青岛市近岸水域及贝类体内酚的分布。在所调查的水域内酚的含量范围为０－８．１１μｇ／Ｌ,平均值为１．５５μｇ／Ｌ。 相似文献
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条纹石鮨摄食强度与代谢及能量收支间的关系 总被引：1，自引：0，他引：1
设日摄食率为０．４％、１．５％、４．０％三种水平,分别测定条纹石鱼旨Ｍｏｒｏｎｅｓａｘａｔｉｌｉｓ幼鱼的代谢及能量的收支情况。处于饱食（日摄食率４．０％）及维持状态（日摄食率１．５％）下,该鱼代谢率增加的峰值分别于摄食后３ｈ及７ｈ内出现,为静止时代谢水平的２．１０倍和２．４６倍,ＳＤＡ（特殊动力作用）持续时间均为２１ｈ,ＳＤＡ总耗能量分别占摄入能的１３％和３５．８％。条纹石鱼旨在饱食时的转化效率Ｋ（湿重）为２０．８５％。三种摄食水平下条纹石鱼旨的能量收支方程分别为：饱食状态（日摄食率４．０％）时,１００Ｃ＝８．４Ｆ＋７．８Ｕ＋１３．０ＳＤＡ＋３６．９（Ｒｓ＋Ｒａ）＋３３．９Ｇ;维持状态（日摄食率１．５％）时,１００Ｃ＝７．８Ｆ＋４．１Ｕ＋３５．８ＳＤＡ＋５２．３（Ｒｓ＋Ｒａ）,其中Ｇ＝０;减重状态（日摄食率０．４％）时,（Ｆ＋Ｕ＋Ｒ）／（Ｃ＋Ｐ１）＝６７．３％,其中Ｃ＋Ｐ１＝１４．４Ｃ＋８５．６Ｐ１,Ｆ＋Ｕ＋Ｒ＝１．８Ｆ＋８．１Ｕ＋５７．４Ｒ。 相似文献
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溴氰菊酯对草鱼种的急性毒性试验 总被引：12，自引：0，他引：12
水温２２±１℃时,溴氰菊酯对草鱼种的行为影响明显,中毒症状随浓度增减和作用时间长短而表现出差异。溴氰菊酯对草鱼种９６ｈＬＣ５０为２１６μｇ／Ｌ,９５％置信区间为１９３—２４２μｇ／Ｌ,剂量—效应关系回归方程为ｙ＝１．５２＋１０．４０ｘ。估算安全浓度为０２１６μｇ／Ｌ。 相似文献
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对虾养殖实验围隔中的固氮作用及其氮输入 总被引：2，自引：0，他引：2
１９９７年６～１０月,以乙炔还原法进行了不同放养模式下对虾养殖实验中生物固氮作用的测定。结果表明,各围隔中,对虾单养（Ｙ－４）和对虾＋海湾扇贝（Ｙ－５）的固氮作用较高,均值分别为２．６２μｇＮ／（Ｌ·ｈｒ）和２．６５μｇＮ／（Ｌ·ｈｒ）;对虾＋罗非鱼＋缢蛏（Ｔ－５）的最低,为１．５３μｇＮ／（Ｌ·ｈｒ）,对虾＋缢蛏（Ｙ－６）和对虾＋罗非鱼（Ｙ－７）的分别为２．３０μｇＮ／（Ｌ·ｈｒ）和１．８９μｇＮ／（Ｌ·ｈｒ）。各围隔中固氮速率较高与水体有效氮含量较低及有效氮磷比值不高有关。水层固氮蓝藻主要为蓝球藻（Ｃｈｒｏｃｏｃｕｓ）和念珠藻（Ｎｏｓｔｏｃ）。估算各围隔实验期间固氮作用输入分别为Ｙ－４∶１７．７２ｇ;Ｙ－５∶１９．６３ｇ;Ｙ－６∶９．０５ｇ;Ｙ－７∶１０．５９ｇ;Ｔ－５∶７．９９ｇ。 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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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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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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