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1.
利用海水陆基实验围隔优化了三疣梭子蟹(Portunus trituberculatus)、凡纳滨对虾(Litopenaeus vannamei)、菲律宾蛤仔(Ruditapes philippinarum)和菊花江蓠(Gracilaria lichevoides)的混养结构。实验设6个处理组,分别为蟹-虾(CS)、蟹-虾-贝(CSB)、蟹-虾-贝-藻(CSBJ1、CSBJ2和CSBJ3),以梭子蟹单养为对照(C),每个处理组设置了4个重复。结果表明,各处理组梭子蟹个体规格差异不显著(P0.05),产量以CSBJ2处理组最高;CSBJ1和CSBJ2组凡纳滨对虾的平均体重、特定生长率以及成活率均显著高于其它处理组(P0.05);凡纳滨对虾产量以CSBJ2最高,显著高于其它处理组(P0.05);混养江蓠处理组菲律宾蛤仔成活率显著提高,但产量与其它处理差异不显著;养殖期间,CSBJ2处理组亚硝氮含量总体上显著低于其它处理(P0.05),混养江蓠各处理水体氨氮浓度养殖后期均显著降低(P0.05),而CSBJ1和CSBJ2组总氮和总磷浓度在中后期显著低于其它处理(P0.05)。本研究表明,虾蟹贝混养系统中搭配适宜密度的菊花江蓠,可以有效改善水质,减少水体中总氮、总磷浓度以及氨氮、亚硝氮等有害物质含量,提高梭子蟹和对虾的产量和成活率及菲律宾蛤仔的成活率。在本研究条件下,虾、蟹、贝和江蓠混养的最佳配比为三疣梭子蟹6ind/m2,凡纳滨对虾45ind/m2,菲律宾蛤仔30ind/m2和菊花江蓠0.36kg/m2。 相似文献
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本试验研究改良了池塘水质环境,预防了疾病的发生和避免了虾蟹相残,使以虾为主的虾、蟹、藻混养试验池与对虾单养对照池的对虾成活率大体接近,实现亩均综合产量222.05kg,亩均产值6985.13元,亩均盈利2472.61元,是一种高产、优质、高效的多元化养殖模式。 相似文献
3.
《中国渔业质量与标准》2015,(3)
采用18个36 m2的围隔进行对虾单养和对虾–罗非鱼混养实验,利用N、S、P综合相对污染指数对单养和混养围隔底质有机负荷进行研究。实验分为6组,每组3个围隔。各围隔放养体长为(0.45±0.01)cm的凡纳滨对虾3 000尾,放养体重为(201±25)g的罗非鱼分别为0(Ⅵ组)、4(Ⅰ组)、8(Ⅱ组)、12(Ⅲ组)、18(Ⅳ组)和24尾(Ⅴ组),放养对虾1个月后再放养罗非鱼。实验期间各围隔均不进行水交换,实验周期为70 d。结果表明,各围隔底质中N、P、S呈现显著上升趋势,但对虾-罗非鱼混养围隔底质中N、P、S的积累量均小于对虾单养围隔。其中,Ⅲ组的N、P、S增长率最小。各组围隔相对污染指数排列如下:Ⅵ(10.78)Ⅴ(8.30)Ⅰ(7.68)Ⅳ(7.40)Ⅱ(6.09)Ⅲ(4.12),其中Ⅲ组的相对污染指数显著小于Ⅵ组(P0.05)。Ⅲ组为本实验的效果最佳组,即混养最佳配比为凡纳滨对虾8.3×105尾/hm2、罗非鱼3 320尾/hm2,罗非鱼均重为(201±25)g/尾。本研究可为对虾–罗非鱼混养中选定合适的养殖容量提供参考。 相似文献
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不同养殖模式及光照对凡纳滨对虾生长和水质的影响 总被引：1，自引：0，他引：1
利用室内水泥池4种不同养殖模式(虾单养或混养不同鱼类)和2种光照(自然光和弱光)对凡纳滨对虾生长、产量和水质的影响开展了研究。试验共设6个试验组,2个对照组,每个组别共设3个重复:自然光虾单养组、弱光组对虾单养、自然光虾鳅混养、弱光虾鳅混养、自然光虾鲢混养、弱光组虾鲢混养、自然光虾鳅鲢混养、弱光虾鳅鲢混养,养殖70d。测定试验前后试验池虾规格、总质量、存活率及饵料系数和鱼的规格、总质量。每隔15~20d测定水质指标。试验结果表明,单养组的虾自然光条件下规格显著大于其他组(P0.05),而弱光单养组的虾规格显著小于其他组(P0.05),其他组别差异不显著(P0.05)。饵料系数方面,单养组显著大于混养组(P0.05),存活率混养组显著高于单养组(P0.05),自然光组饵料系数和存活率显著高于弱光组(P0.05)。水质方面,养殖期间各组的硝态氮、亚硝态氮、氨氮呈稳步上升趋势,但亚硝态氮质量浓度,虾单养组和虾鳅混养组均显著高于虾鲢混养组和虾鳅鲢混养组(P0.05),自然光组显著低于弱光组(P0.05),氨氮,虾单养组显著高于其他组(P0.05),自然光组低于弱光组(P0.05)。试验结果显示,适当的光照是凡纳滨对虾生长的重要因素,泥鳅能大幅提高池塘经济效益节约成本,而鲢鳙鱼可有效地改善水质,当泥鳅以及鲢鳙鱼共同混养在虾池时,保证对虾池水质良好的同时,可提高对虾养殖的产量。 相似文献
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对虾,青蟹,江蓠混养试验研究 总被引：2，自引：0，他引：2
本试验研究改良了池塘水质环境，预防了疾病的发生和避免了虾蟹相残，使以虾为主的虾、蟹、藻混养试验池与对虾单养对照池的对虾成活率大体接近，实现亩均综合产量２２２．０５ｋｇ，亩均产值６９８５．１３元，亩均盈利２４７２．６１元，是一种高产、优质、高效的多元化养殖模式。 相似文献
6.
海水池塘虾、蟹混养效果的初步研究 总被引：1，自引：0，他引：1
1998年与1999年间在汕尾市红草养殖池塘进行了虾蟹混养及虾单养对比试验。结果表明无论从水质、产量还是成活率来看，混养都优越于单养。其中从效益来看池塘虾蟹混养的盈利可比池塘对虾单养提高50—100％。 相似文献
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不同单养和混养海水实验围隔浮游生物的研究 总被引：1，自引：0，他引：1
1995年6～10月和1996年6～8月对中国对虾单养及其与台湾红非鲫、菲律宾蛤仔、海湾扇贝或缢蛏的不同混养实验围隔浮游生物的研究结果表明:养殖管理措施和放养种类对围隔浮游生物种类和生物量都会产生一定影响,其中前者往往具主要作用。投饵养殖时围隔浮游植物以20μm以下的种类为主,生物量较低,其中混养台湾红非鲫的围隔叶绿素a(Chl-a)相对较高,混养菲律宾蛤仔的围隔Chl-a较低;在投饵的基础上施肥后甲藻等鞭毛藻类易大量发生成为优势种,浮游植物生物量较单纯投饵时有所升高,但单养和混养对围隔Chl-a的影响不明显。非鲫捕食往往导致大型桡足类在浮游动物生物量中的比例下降,贝类则通过食物竞争同时使桡足类生物量降低和种类小型化,由于非鲫与海产贝类的食物灶存在一定分化,二者混养至少对贝类有利,因此鱼虾贝混养应较鱼虾混养或虾贝混养效果更好。 相似文献
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不同单养和混养海水实验围隔初级生产力的研究 总被引：3，自引：1，他引：2
１９９５年和１９９６年夏秋季进行的围隔实验表明投饵养殖时浮游植物毛初级生产力较低,水呼吸相对较高,多数围隔中毛初级生产力／水呼吸〈１,其中混养中国对虾和台湾红罗非鱼的围隔中毛初级生产力较高,而混养中国对虾,台湾红罗非鱼和菲律宾蛤仔的围隔中毛初级生产力最低;在投饵基础上酌情施肥后围隔毛初级生产力同于投饵养殖时,毛初级生产力／水呼吸〉１,但单养中国对虾,对虾与罗非鱼混养和对虾与海湾扇贝或缢蛏混养的围隔 相似文献
9.
以18个海水池塘陆基围隔进行对虾池塘不同密度混养牡蛎试验,利用N、S、P综合相对污染指数对不同密度混养牡蛎对虾池塘底质养殖负荷进行评估,结果表明,混养牡蛎虾池底质中N、S、P营养指标随养殖进程呈上升趋势,到实验结束时,不同密度梯度牡蛎混养围隔底质污染程度不同,根据N、S、P综合相对污染指数评估养殖负荷,各围隔呈低谷状排列:Ⅱ组(98.14)>Ⅲ组(60.64)>Ⅳ组(33.05)>Ⅴ组(29.68)<Ⅵ组(126.85);不同密度处理中,位于谷底的Ⅴ组为最佳放养密度点,对于养殖密度为4.5×106尾/hm2的对虾池塘,混养牡蛎最佳生物量为1003.2g/m3,转换为生产规模,则混养牡蛎最佳生物量为1.01×104kg/hm2。 相似文献
10.
本试验研究改良了池塘水质环境，预防了疾病的发生和避免了虾蟹相残，使以虾为主的虾、蟹、藻混养试验池与对虾单养对照池的对虾成活率大体接近。试验塘和对照塘均养两造，试验塘年亩均综合产量222．05kg；亩均产值6085．13元，亩均盈利2472．61元。 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
13.
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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