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缢蛏等贝类食品脂质脂肪酸组成分析研究 总被引：2，自引：0，他引：2
贝类食品的脂质与陆生动植物的脂质相比,前者脂肪酸组成复杂,有含量相当高的长碳链w_3族高度不饱和脂肪酸,尤其是廿碳五烯酸(EPA)和廿二碳六烯酸(DHA),对治疗心血管疾病有一定的疗效。本文对缢蛏等十三种贝类脂质中脂肪酸组成进行了分析,目的为食品营养研究和贝类资源的开发利用提供基本数据。 相似文献
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贝毒监测与预报及其在决策中的应用 总被引：2，自引：0，他引：2
1 贝毒带来的损失生活在海洋中的贝类 ,其食物主要来自于海水中的单细胞藻类。在众多的单细胞藻类中 ,有些种类是有毒的 ,当贝类摄入有毒单细胞藻类或者其休眠孢子后 ,藻类毒素会在贝类体内累积 ,使贝类具有毒性 ,即贝毒。目前对人类危害严重的主要有麻痹性贝毒(ＰａｒａｌｙｔｉｃＳｈｅｌｌｆｉｓｈＰｏｉｓｏｎｉｎｇ,ＰＳＰ) ,腹泻性贝毒 (Ｄｉａｒ ｒｈｅｔｉｃＳｈｅｌｌｆｉｓｈＰｏｉｓｏｎｉｎｇ ,ＤＳＰ) ,失去记忆性贝毒 (Ａｍ ｎｅｓｉｃＳｈｅｌｌｆｉｓｈＰｏｉｓｏｎｉｎｇ,ＡＳＰ) ,神经性贝毒 (ＮｅｕｒｏｔｏｘｉｃＳｈ… 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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近江牡蛎等3种贝类的脂类成分分析 总被引：2，自引：0，他引：2
分析3种贝类的脂类成分,以期为贝类的高值化加工利用提供基础数据。采用氯仿甲醇法提取近江牡蛎、波纹巴菲蛤和马氏珠母贝中的脂质成分,分析脂质中的胆固醇和磷脂含量,采用液液萃取技术分离中性脂和极性脂,并用GC-MS分析其脂肪酸组成。研究结果表明,3种贝类的粗脂肪含量基本在1%左右;脂质成分中胆固醇含量在0.07~0.12 mg/g;脂质中磷脂含量在14%~34%,极性脂含量在27%~45%;脂质中EPA和DHA总含量在12%~22%,近江牡蛎和波纹巴菲蛤脂质中EPA含量高于DHA,而马氏珠母贝脂质中DHA含量高于EPA。 相似文献
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本文介绍用紫外线法消毒的海水对文蛤、花蛤、缢蛏进行净化的中试生产工艺技术及其净化效果。通过对该三种净化贝净化前后的各种安全指标以及其净化过程中大肠菌群数和砂份含量随时间的变化进行检测,认为原料符合SC/T 3013-2002规范的文蛤、缢蛏、花蛤经24小时的净化其大肠菌群都能达到DB35/575-2004净化海水贝类标准的要求(≤300MPN/100g贝肉),同时大肠群菌数较低的贝类可以缩短净化时间;根据其含砂量的不同净化时间可控制在8~16小时;要通过净化来大量降低贝类的重金属、农药及贝毒的含量似乎是不可能的;根据贝类品种的不同,其净化过程的死亡率在1.1~3.5%,产品得率90~98%;其净化产品在8℃~10℃贮存与流通可贮藏7天。 相似文献
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缢蛏产于我国和日本,是我国海涂养殖的一种重要经济贝类,但关于它的人工控制产卵的工作却做得很少。我室连续在1958和1959两年间进行缢蛏生殖的研究时,曾多次引用岩田清二,Galtsoff,P.S.[4-6]及郭继绪等人用于其他贝类的人工控制产卵方法来控制缢蛏产卵,如采用KCl,NH4OH,膘胨、淀粉等各种化学药品,做成海水溶液进行注射或浸泡亲贝;用提高水温刺激、感应电流刺激、以及放入缢蛏的精子或卵子做成的海水悬浮液诱导,均不能引起缢蛏产卵放精的反应。 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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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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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
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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