硫丹对水生生物毒理效应的研究进展

硫丹是一种有机氯杀虫剂,广泛应用于蔬菜、水果、茶叶、棉花、烟草、林木等害虫的防治.然而,在杀灭害虫、提高农产品产量的同时,硫丹也会对非目标生物,特别是对栖息在水环境中的生物体产生一定影响.本文综述了硫丹对水生生物急、慢性毒理效应,初步归纳了硫丹影响水生生物代谢的机制,阐述了硫丹在水体、底泥和生物体中的分布情况,旨为评价硫丹在水生生态系统中的环境行为及其对人类健康风险提供科学依据.     

中国水生生物资源养护行动纲要

我国海域辽阔，江河湖泊众多，为水生生物提供了良好的繁衍空间和生存条件。受独特的气候、地理及历史等因素的影响，我国水生生物具有特有程度高、孑遗物种数量大、生态系统类型齐全等特点。我国现有水生生物2万多种，在世界生物多样性中占有重要地位。以水生生物为主体的水生生态系统，在维系自然界物质循环、净化环境、缓解温室效应等方面发挥着重要作用。丰富的水生生物是人类重要的食物蛋白来源和渔业发展的物质基础。养护和合理利用水生生物资源对促进渔业可持续发展、维护国家生态安全具有重要意义。为全面贯彻落实科学发展观，切实加强国家生态建设，依法保护和合理利用水生生物资源，实施可持续发展战略，根据新阶段、新时期和市场经济条件下水生生物资源养护管理工作的要求，制定本纲要。     

水生生物毒

水生生物本身所具有的有毒物质称为水生生物毒，它并非是水生生物死后受细菌沾染所生成的有毒物质，而是它活着时就含有的物质。国内对于水生生物毒引发的食物中毒以及环境污染等问题曾有记载。有关水生生物毒之研究在日本、美国等甚为盛行，还有许多论著、综述等发表。随着水产事业的发展，对于水生生物毒的认识与研究是刻不容缓的课题。     

陕西省水生野生动物资源保护现状与对策分析

生态环境建设,是21世纪人类面临的共同主题,是实现经济社会可持续发展的重要基础。水生野生动植物是生态系统中的重要组成部分。水生野生动植物每一物种,在生态系统中都占有各自特定的地位。与生态系统中的其他生物和非生物互为依赖,共同维持生态平衡。随着一个物种的消失,将导致若干物种的灭绝,直至造成整体生态系统平衡的改变。水生野生动植物对环境的变化比陆生动     

《中国水生生物资源养护行动纲要》

(2006年2月14日)我国海域辽阔,江河湖泊众多,为水生生物提供了良好的繁衍空间和生存条件。受独特的气候、地理及历史等因素的影响,我国水生生物具有特有程度高、孑遗物种数量大、生态系统类型齐全等特点。我国现有水生生物2万多种,在世界生物多样性中占有重要地位。以水生生物为主体的水生生态系统,在维系自然界物质循环、净化环境、缓解温室效应等方面发挥着重要作用。丰富的水生生物是人类重要的食物蛋白来源和渔业发展的物质基础。养护和合理利用水生生物资源对促进渔业可持续发展、维护国家生态安全具有重要意义。为全面贯彻落实科学发…     

水污染生物学-一门日益引起人们注意的学科

水污染生物学既是水生生物学的一个分支，又是环境生物学的重要组成部分。它研究受污染水体中生物个体、种群、群落与生态系统的结构和功能，以及它们的发生和演变的规律；污染水环境中生物之间、生物与污染环境之间的相互关系，从而为保护水环境服务。     

水生生物环境丰容技术及其应用研究进展

水生生物作为人类生活的重要组成部分,其在养殖、运输以及展示等过程中福利水平低下现象层出不穷,寻求合适的方法来解决水生生物福利低下的问题,成为保障并提升水生生物福利的一大重要工作。环境丰容作为一项能够通过对圈养动物生存环境进行优化,提升圈养动物福利水平,使得圈养动物获得生理和心理健康,展示其自然行为的技术,成为保障和提升水生生物福利的一个重要手段。目前,与国外相比,国内对水生生物环境丰容技术的研究还处于起步阶段,如何利用环境丰容技术改善水生生物的生存环境,保障并提升水生生物福利水平日益成为研究热点。为此,本文综述了环境丰容的定义、发展历程、环境丰容与动物福利的关系以及在水生生物中的4种主要环境丰容技术。同时,就水生生物环境丰容技术存在的问题进行讨论并提出建议,以期为水生生物环境丰容提供更多方案参考和理论支撑。     

活性污泥膨胀的影响因素

渔业生产是以水生经济动物植物作为其生产对象的,这些水生经济动植物的繁殖生长发育每一阶段都必须在特定的环境条件下才能完成.鱼虾蟹贝藻类储存量的增减,质量优劣都直接受渔业水域环境变化的影响,从而间接对渔业生产产生影响.因此,渔业水域环境是水生经济动植物赖以形成和发展的重要条件,保护渔业水域实际是保护整个渔业经济水生生物生态系统,同时也是维持渔业可持续发展的基本前提. 　　……     

贯彻落实《中国水生生物资源养护行动纲要》的思考

水生生物资源属于自然资源的一部分,丰富的水生生物是人类生存和发展的重要食物蛋白来源和渔业发展的物质基础;以水生生物为主体的水生生态系统,在维系自然界物质循环、净化环境、缓解温室效应等方面发挥着重要作用;养护和合理利用水生生物资源对促进天津渔业可持续发展,把天津     

贯彻落实《中国水生生物资源养护行动纲要》的思考

水生生物资源属于自然资源的一部分,丰富的水生生物是人类生存和发展的重要食物蛋白来源和渔业发展的物质基础;以水生生物为主体的水生生态系统,在维系自然界物质循环、净化环境、缓解温室效应等方面发挥着重要作用;养护和合理利用水生生物资源对促进渔业可持续发展、维护生态安全等方面具有重要意义。     

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.     

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.     

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.     

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.     

Growth hormone (GH) and reproduction: a review

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.     

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.     

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.