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1.
论我国水产养殖业的发展方向 总被引：2，自引：0，他引：2
改革开放20多年来,我国渔业发展取得了举世瞩目的成就。2006年,水产品总量约5290万吨,连续16年居世界第一,占世界1.3亿万吨产量的40%。水产品进出口总额达到136.6亿美元,其中水产品出口量为301.5万吨,出口额为93.6亿美元,占世界水产品出口的10%,占我国农产品出口总额的30%,继续居我国大宗农产品出口首位。2006年我国水产养殖产量达到了3597万吨,占我国渔业总产量的68%,占世界水产品养殖总产量的70%,是目前唯一养殖产量超过捕捞产量的国家。全国从事水产养殖的劳动力达1000万人。 相似文献
2.
《水利渔业》2005,(2)
20 0 4年我国水产品出口大幅增长2 0 0 4年 ,我国水产品出口大幅增长 ,出口量和出口额分别达到 2 4 2 .1万t、6 9.7亿美元 ,同比分别增长 15 .1%和 2 7% ;实现贸易顺差 37.3亿美元 ,同比增长 2 4 .3%。水产品出口占农产品出口总额的 2 9.7% ,继续居大宗出口农产品首位。鳗鱼、对虾、罗非鱼、大黄鱼、贝类等养殖名优水产品成为主要出口品种 ,占出口总额的比重由 2 0 0 3年的 2 9%升至 2 0 0 4年的 34%。水产品加工贸易出口额达 2 5 .9亿美元 ,同比增长 32 .7% ,占水产品出口总额的 37.2 %。2 0 0 4年我国水产品对日、美、欧、韩出口额所占份… 相似文献
3.
《科学养鱼》2004,(7):54-55
虾类取代鳗鱼成为我国水产品出口创汇第一品种2003年我国水产品对外贸易克服非典疫情影响,出口额再创新高,占农产品出口总额214.3亿美元的25.6%,继续位居大宗出口农产品首位。据海关统计,去年我国水产品进出口总额达79.7亿美元;其中出口额54.9亿美元,同比增长了17%,实现贸易顺差30.1亿美元。水产品出口量微增而出口额却增长17%,与国际水产品市场价格上扬有关,同时也得益于我国出口品种结构的调整和产品加工深度的提高。虾类、鳗鱼、罗非鱼、大黄鱼等名特优养殖水产品出口额已占一般贸易出口总额的47%。其中,虾类产品出口增长迅猛,已超过鳗鱼… 相似文献
4.
5.
《渔业现代化》2003,(1)
20 0 2年我国渔业发展特点2 0 0 2年我国渔业经济继续保持较好的发展势头 ,1～ 1 1月 ,水产品产量达 371 3.7万吨 ,同比增长 3.9%。水产养殖业继续成为各地农业产业结构调整的重点 ,远洋渔业取得新的进展 ,公海大洋性渔业发展较快 ,近海捕捞产量继续负增长 ;水产品市场平稳 ,总体价格继续走低 ,波动幅度明显减弱 ;水产品进出口贸易保持稳步增长。 1～ 1 1月份 ,我国水产品出口量 1 90万吨 ,出口额 41 .7亿美元 ,同比增长 6%和 1 3.5 % ,出口额占全国农产品出口总额的 2 5 .9% ,继续位居农产品首位。獐子岛大力发展金枪鱼捕捞和加工最近 ,獐… 相似文献
6.
1鳗业在我国水产品国际贸易中的地位2004年我国淡水鳗养殖产量超过13万吨,占世界总产量三分之二以上,产值超过10亿美元,出口创汇8·52亿美元,占全国水产品出口总额的12·2%,位居我国单项农产品出口第一,发展淡水鳗养殖对出口创汇促进水产品国际贸易意义重大。2长乐市养鳗概况及 相似文献
7.
推进水产养殖法制建设促进养殖管理水平的提高 总被引：1，自引：0，他引：1
目前,随着世界性渔业资源的普遍衰退,水产养殖在丰富国内外水产品市场、增加农民收入方面发挥着越来越重要的作用。2001年,世界渔业总产量为1.29亿吨,其中捕捞产量9100万吨 ,养殖产量3750万吨,呈上升趋势。中国渔业发展较快,2002年全国水产品总量4565万吨,其中水产养殖产品占水产品总量的比重从20年前的28.9%升至62%。水产品出口量208.5万吨,出口额46.9亿美元。出口额占全国农产品出口总额181.4亿美元的25.9%,居农产品创汇之首。养殖业的发展为农村提供了大量的就业和增收的机会。1980年以来,从事渔业的劳动力增加了1000多万人,平均每年增加… 相似文献
8.
9.
1我国水产品生产和出口现状1.1从捕捞为主到养殖为主 历史上,我国渔业是以捕捞为主,直至上世纪70年代末,捕捞产量仍占70％以上。90年代初情况发生了变化,养殖产量开始超过捕捞产量。到2001年底,我国水产养殖产量达到2 726万t,占水产品总产量的比重上升到 62％,养殖水产品出口15亿美元,占出口总额的近40％,全国从事水产养殖的劳动力达1000万人。现在,全世界的养殖水产品有70％产自中国。水产养殖业拓展了我国渔业的发展空间,促进了农村、渔区产业结构调整,成为广大渔民、农民就业和增加收入的一个重要领域。水产养殖证制度的建立,既是以联产承包为主要内容的我国水产养殖经营方式的制度化和法律化,也是对渔民、农民开发全民所有制滩涂水面,发展水产养殖业 相似文献
10.
2005年,江西省渔业经济继续保持平稳、持续、健康发展的运行轨迹,渔业经济规模继续扩大、渔业经济质量明显提高、水产品出口继续上升、渔民增收持续提速。全省水产品总量达到168.36万吨,同比增加12.02万吨,增长7.7%;名优水产品完成60.43万吨,同比增加8.98万吨,增长17.5%;养殖面 相似文献
11.
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
12.
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
13.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 
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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
14.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献
15.
Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load 下载免费PDF全文
下载免费PDF全文 Franz Lahnsteiner 《Aquaculture Research》2017,48(7):3901-3909
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos. 相似文献
16.
T. Citarasu K. Venkatramalingam M. Micheal Babu R. Raja Jeya Sekar M. Petermarian 《Aquaculture International》2003,11(6):581-595
The indiscriminate use of antibiotics and chemicals in shrimp hatcheries has led to biomagnification and that in turn could
lead to rejection of a whole consignment. The application of the bioencapsulation technique as a tool for curative treatment
in shrimp larvae was investigated. Herbs having antibacterial properties such as Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia (methanolic extracts) were bioencapsulated in Artemia and fed to Penaeus monodon post larvae PL 1–25. The post larvae were reared in a medium inoculated with pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Vibrio sp. Post larvae reared in the non-inoculated water and fed with non-enriched Artemia exhibited 90% survival, highest specific growth rate (12.43%) and reduced bacterial load. P. monodon reared in the bacterial inoculated water and fed with the non-enriched Artemia exhibited the lowest survival (10–30%), specific growth rate (8.42–9.1%) and increased bacterial load (2.86 × 103 to 3.76 × 105 cfu/g). The methanolic extracts of the herbs helped to increase survival and specific growth rate and reduced bacterial load
in the P. monodon culture system. Among the three herbal extracts, P. corylifolia enriched Artemia fed post larvae showed the tendency to higher survival (>50%), growth rate (11.5 averaged) and low bacterial load (1.12 × 105 cfu/g).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
Effects of cortisol on hepatic carbohydrate metabolism and responsiveness to hormones in the sea raven,Hemitripterus americanus 总被引：2，自引：0，他引：2
The sea raven, Hemitripterus americanus, is a sit-and-wait, low metabolic rate, marine teleost. The objective of this study was to determine i) whether cortisol implantation (50 mg. kg-1) for 7 days altered hepatocyte metabolism, and hepatocyte responsiveness to epinephrine, glucagon and insulin, and ii) whether 8 weeks of food-deprivation modified the above response. Cortisol implantation significantly increased hepatocyte
total glucose production and oxidation from alanine compared to the sham group. There was no cortisol effect on glycogen breakdown,
suggesting that the activation of other pathways, including gluconeogenesis, are required to account for the increased glucose
production. Epinephrine-mediated (10-5M) glycogen breakdown and insulin-mediated (10-8M) total glucose production were enhanced in hepatocytes of cortisol implanted sea ravens, but there were no change in any
glucagon (10-7M) effects. The enhanced glycogen breakdown in the absence of similar increases in total glucose production with epinephrine
indicates mobilization of carbohydrate reserves for endogenous use by the liver.
Food-deprivation for 8 weeks significantly decreased condition factor, plasma cortisol concentration and liver glycogen content
in the sea raven, but had no effect on plasma glucose concentration. Hepatocyte total glucose production and flux rates from
alanine increased significantly with food-deprivation. Moreover, food-deprivation increased responsiveness of total hepatocyte
glucose production to the actions of glucagon and insulin, but not to epinephrine; none of these effects were modified by
cortisol implantation.
Our results indicate that cortisol in the sea raven exerts both a direct and an indirect or permissive effect on hepatocyte
metabolism by modifying hepatocyte responsiveness to epinephrine and insulin stimulation. Cortisol implantation did not modify
the effects of glucagon or food-deprivation in this species. 相似文献
18.
Simulation and quantification of enrichment and retention processes in the southern Benguela upwelling ecosystem 总被引：2，自引：0，他引：2
CHRISTOPHE LETT CLAUDE ROY ANNE LEVASSEUR CARL D. VAN DER LINGEN CHRISTIAN MULLON 《Fisheries Oceanography》2006,15(5):363-372
Important environmental processes for the survival and recruitment of early life stages of pelagic fishes have been synthesized through Bakun's fundamental triad as enrichment, concentration and retention processes (A. Bakun, 1996, Patterns in the Ocean. Ocean Processes and Marine Population Dynamics. San Diego, CA, USA: University of California Sea Grant). This conceptual framework states that from favourable spawning habitats, eggs and larvae would be transported to and/or retained in places where food originating from enrichment areas would be concentrated. We propose a method for quantifying two of the triad processes, enrichment and retention, based on the Lagrangian tracking of particles transported within water velocity fields generated by a three‐dimensional hydrodynamic model. We apply this method to the southern Benguela upwelling ecosystem, constructing putative maps of enrichment and retention. We comment on these maps regarding main features of the circulation in the region, and investigate seasonal variability of the processes. We finally discuss the results in relation to available knowledge on the reproductive strategies of two pelagic clupeoid species abundant in the southern Benguela, anchovy (Engraulis encrasicolus) and sardine (Sardinops sagax). Our approach is intended to be sufficiently generic so as to allow its application to other upwelling systems. 相似文献
19.
This study evaluated the effects of three levels of loading density (200, 300 and 400 g L−1) and four levels of duration (1, 3, 6 and 9 h) on the mortality, plasma cortisol and chloride levels and growth of rohu Labeo
rohita fingerlings in a transport simulation. While total immediate mortality was low (4–12%), delayed mortality was high (27–49%).
Initial capture and handling were found to constitute the most stressful phase as indicated by elevated plasma cortisol. The
levels of cortisol continued to rise at 6 and 9 h after transport, with the highest level observed at 9 h after transport.
The level of plasma chloride fell after transport across all density levels and treatment durations. Specific growth rate
(SGR, %/day) and total bacterial density (cfu/g) were not different between and within treatments, and between treatments
and the controls. This study demonstrates that transport has a profound effect on the stress responses of rohu fingerlings.
Although the level of immediate mortality was low, the higher level of delayed mortality has serious implications in terms
of production inefficiency for grow-out farmers. 相似文献
20.
Gabrielle C. Canonico Angela Arthington Jeffrey K. McCrary Michele L. Thieme 《水产资源保护:海洋与淡水生态系统》2005,15(5):463-483
- 1. The common name ‘tilapia’ refers to a group of tropical freshwater fish in the family Cichlidae (Oreochromis, Tilapia, and Sarotherodon spp.) that are indigenous to Africa and the southwestern Middle East. Since the 1930s, tilapias have been intentionally dispersed worldwide for the biological control of aquatic weeds and insects, as baitfish for certain capture fisheries, for aquaria, and as a food fish. They have most recently been promoted as an important source of protein that could provide food security for developing countries without the environmental problems associated with terrestrial agriculture. In addition, market demand for tilapia in developed countries such as the United States is growing rapidly.
- 2. Tilapias are well‐suited to aquaculture because they are highly prolific and tolerant to a range of environmental conditions. They have come to be known as the ‘aquatic chicken’ because of their potential as an affordable, high‐yield source of protein that can be easily raised in a range of environments — from subsistence or ‘backyard’ units to intensive fish hatcheries. In some countries, particularly in Asia, nearly all of the introduced tilapias produced are consumed domestically; tilapias have contributed to basic food security for such societies.
- 3. This review indicates that tilapia species are highly invasive and exist under feral conditions in every nation in which they have been cultured or introduced. Thus, the authors have concluded that, despite potential or observed benefits to human society, tilapia aquaculture and open‐water introductions cannot continue unchecked without further exacerbating damage to native fish species and biodiversity. Recommendations include restricting tilapia culture to carefully managed, contained ponds, although exclusion is preferred when it is feasible. Research into culture of indigenous species is also recommended.