鲤鱼脑垂体中促性腺激素含量的周年变化

经丙酮干制的垂体粉用40％乙醇抽提，冷冻干燥，用放射免疫测定法测定鲤鱼垂体中促性腺激素含量的周年变化。年平均含量为56．1微克／毫克。2月份临近产卵期时，雌、雄鲤鱼垂体中的促性腺激素含量都达到最大值(雌鱼为154．0微克／毫克，雄鱼为160．0微克／毫克)。雄鱼9月份含量最低(8．3微克／毫克)，雌鱼10月份含量最低(3．8微克／毫克)，并分别在10月份和11月份后开始逐渐上升。其周年变化并与其性腺的发育成正相关关系。     

瓯江彩鲤肌肉营养成分分析

瓯江彩鲤肌肉中蛋白质的含量为18．04％，水分76．61％，灰分1．28％，脂肪2．37％(以上均为鲜重百分比)。肌肉中含有17种氨基酸[总量为770．9mg/g(干重)]；其中，人体必需氨基酸9种[总量为333．5mg/g(干重)]；甘氨酸、丙氨酸、天门冬氨酸及谷氨酸等鲜味氨基酸的含量较高，共330．0mg/g(干重)。此外，还含有适量的钙、铁、锌、硒等矿物元素，锌的含量[16．15mg/kg(鲜重)]高于一般的淡水鱼类。因此，瓯江彩鲤是一种营养价值较高的食用鱼类，宜推广养殖和加工利用。     

鼠尾藻粉脆片的配方研究

<正>鼠尾藻(Sargassum thunbergii),隶属于褐藻门、圆子纲、墨角藻目、马尾藻科、马尾藻属。主要分布潮间带,为优势种,北起辽东半岛、南至雷州半岛均有分布。鼠尾藻蛋白质含量高于海带及裙带菜,脂肪含量较低,氨基酸较全面、呈味氨基酸含量丰富,钾、钙等无机元素含量高,本身具有独特的气味。鼠尾藻中含有大量粗纤维和膳食纤维,其中膳食纤维含量达到196克/千克。膳食纤维是植物性食物中人胃肠道不能消化的多糖类物质的统称,虽然不能被消化     

用有机物营养液培养钝顶螺旋藻的初步探讨

钝顶螺旋藻(Spirolina platensis)是蓝藻门蓝藻纲颤藻科螺旋藻属的一种丝状蓝藻。它的蛋白质含量占干重的65％以上，并由较好的氨基酸组成，含有丰富的人和动物必需的氨基酸。脂肪、糖类、胡萝卜素、维生素及各种微量元素也都很丰富。     

螃蟹的营养、食疗与烹调

一、简介 蟹的种类很多,主要有海水产与淡水产两种。我们经常食用的蟹,海水产的有梭子蟹和青蟹;淡水产的种类较多,有江蟹、河蟹、湖蟹等。 二、营养成分 每100克蟹肉中含蛋白质14克,脂肪2.6克,碳水化合物0.7克,钙141毫克,磷191毫克,铁0.8毫克,维生素A、B_1、B_2,还含有烟酸和10多种游离氨基酸,胡萝卜素138毫克(河蟹达3576微克)。另外还含有甲壳素。 三、性味 性寒、味咸。 四、功效 蟹肉用于清热散结,通脉滋阴,补肝     

白蛤加工

白蛤学名为四角蛤蜊（Mactraveneriformis,Reeue），是我国沿海常见的底栖经济贝类，肉细味美、营养丰富。每百克鲜肉中含蛋白质10．8克、脂肪1·16克、碳水化合物4．6克、钙37毫克、磷82毫克、铁14．2毫克、维生素A400国际单位、硫胺素0．03毫克、梳黄素015毫克、烟酸1．7毫克。100克于品中含碘240微克。蛋白质中含9种人体必需氨基酸且比例适中，属完全蛋白质。脂肪中含脑黄金主要成份DHA（二十二碳六烯酸）3．3％，EPA（二十碳五烯酸）5．5％。中医认为其肉性味咸寒，有滋阴、利水、化痰、软坚功能，可用于水肿、痰积、病块、癌瘤、崩…     

斑点叉尾鮰水霉病的防治技术

斑点叉尾鮰是大型温水性淡水鱼类，最大个体达35千克以上，含肉率高，蛋白质和维生素含量丰富，肉质细嫩，味道鲜美，深受消费者欢迎，在我图北方和南方均有养殖。但在斑点叉尾鮰养殖过程中，极易暴发性地发生水霉病，致死率高达80％-100％。具体情况分析如下：     

栅藻B38营养成分分析及蛋白质营养价值评价

对栅藻B38的营养成分进行了全面分析,结果表明,栅藻藻粉中油脂含量14%,总糖含量13.86%,粗纤维3.52%,灰分4.28%,蛋白质49.0%,为高蛋白质类微藻。栅藻B38中含有23种脂肪酸。栅藻B38中氨基酸总量为852.58 mg/g,必需氨基酸占总氨基酸的47.45%,必需氨基酸指数为85.42%。两种模式的氨基酸比值系数分较接近,均在65以上;待评价物质的氨基酸品质与模式蛋白的贴近度接近1(0.93和0.88)。栅藻B38中共检测出23种矿物质元素,其中钠、钾、钙、镁、铁、铝含量较为丰富。重金属的含量均低于国家食品卫生标准。栅藻B38中维生素B3(106.02 mg/100 g)和维生素E(540.77 mg/100 g)的量较高。综上,栅藻B38的营养较丰富,可以进一步开发利用。     

广西近海捕虾生产现状和资源繁殖保护问题

广西沿海位于北部湾北部，地处亚热带，季风气候，雨量充沛／冬无严寒，夏无酷暑。北海市至围洲海面，海水温度年平均20℃，最高31℃，最低15℃；盐度为27．4—33%。30米等深线内捕虾作业区达二万平方公里，近海营养物质丰富．磷酸盐在100毫克／升左右，溶解氧为6-8毫克／升，底层有机生物质达60-100克／平方米，污染不严重。     

婆罗囊螺与嫁(女戚)的营养成分分析

对婆罗囊螺和嫁的多糖、蛋白质、水分、灰分、脂肪含量以及氨基酸和脂肪酸的组成进行了分析比较。结果表明:婆罗囊螺蛋白质含量为33.79%,脂肪含量为15.48%,氨基酸总量为35.55%,必需氨基酸含量占总氨基酸含量的32.86%,鲜味氨基酸如谷氨酸(17.97%)、天门冬氨酸(11.28%)含量丰富。嫁的蛋白质含量为54.52%,高于婆罗囊螺,含有9.35%的脂肪,所测得的氨基酸占总干重的53.05%,必需氨基酸占氨基酸总量的17.49%。脂肪酸在两种贝类中的含量都很丰富,共测出了25种。总体来说,婆罗囊螺是高脂肪、低蛋白种类。而嫁则是一种高蛋白食品。     

Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean

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.     

Rare serotype occurrence and PFGE genotypic diversity of Streptococcus agalactiae isolated from tilapia in China

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.     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

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.     

Evaluation of a Fast Method Based on the Presence of Two Restriction Sites in the Mitochondrial ND5 (mt ND5) Gene for the Identification of Scomber Species

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.     

Purification and partial characterization of GtHs (cfLH and cfFSH) from Indian walking catfish (Clarias batrachus) (L.) and development of a homologous ELISA for cfLH

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.     

Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection

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).     

The optimal dietary protein level of juvenile silver sillago Sillago sihama at three dietary lipid levels

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.     

Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies

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.