大连市工厂化养殖及网箱养鱼继续扩大

作为大连市渔业新兴优势产业的工厂化养殖和网箱养鱼,2003年持续增速不减,养殖品种不断增加。工厂化养殖面积已达52×104m2,继2002年增加10×104m2的规模后,本年又新增12×104m2。网箱养鱼规模为小网箱8000个、大网箱105个,本年新增大网箱敏多达65个。养殖品种也更趋多样化,已由过去的仅几种发展为大菱鲆、牙鲆、河鲀、欧洲鳎、     

强化水产品质量安全的几点做法

<正>绥中县位于辽宁西部,西与河北省山海关接壤,东与兴城市相邻,海岸线长86 km,水产资源较为丰富,2005年以前以捕捞业为主,2006年后随着大菱鲆养殖业和海参育苗养殖业的发展,目前绥中县大菱鲆养殖面积达到40万m2,有养殖户210家;海参育苗水体20万m3,育苗场家140户,海参增养殖面积达2 666 hm2。大菱鲆和海参育苗养殖年产值达7亿元,绥中县的渔业结构由过去的以捕捞为主转变为以养殖为主,特别是2010年省委决定绥中为省管县,市局的海洋渔业管理职能全部下放到县里,绥中县海洋与渔业行     

圆斑星鲽与大菱鲆养殖效果对比试验

近年来,随着辽宁葫芦岛市渔业园区养殖规模的增加、养殖时间的延长,海水工厂化养殖相继出现种质退化、病害频发、品质下降等现象。为了调整渔业园区养殖品种单一的现状,提高养殖效益,农服中心于2018年4月,在兴城现代渔业园区鑫隆水产养殖有限公司进行"圆斑星鲽与大菱鲆养殖效果对比试验"。从山东引进圆斑星鲽苗种1.35万尾,经过10个月的养殖.     

葫芦岛市工厂化养鱼产值突破亿元

设施渔业作为渔业养殖新的生产方式 ,在我省得到全面推广 ,工厂化面积和产值不断提高。葫芦岛市积极开展工厂化养殖 ,2 0 0 3年 ,该市工厂化养鱼面积达到 19 2× 10 4 m2 ,比上年增加 11 1× 10 4 m2 ,增加了138% ,产量可达 12 5 0t ,产值突破 1亿元。其中海水养鱼面积要比上年     

实施渔业标准化生产规范发展工厂化养殖

近几年来,我市结合渔业结构调整和渔业产业化经营,大力推进渔业标准化生产和无公害水产品行动计划,通过加强领导,搞好监督检查等措施,规范发展以大菱鲆健康生态养殖为重点的水产品工厂化养殖,水产品市场竞争力、水产品质量和渔民收人都得到大幅度提高。2003年,我市大菱鲆有效养殖面积达10hm^2(150亩),大棚131个,存鱼210万尾,共产售大菱鲆680t,销售收人8200万元,创利4000万元。     

大菱鲆海水小瓜虫病的治疗方法

<正>大菱鲆英文名为turbot,英译名(兼商品名)多宝鱼,自1992年被成功引入我国后,经过20年的发展,目前我国大菱鲆养殖面积达400万m2,年产值近40亿元。其中葫芦岛市的大菱鲆养殖面积达230万m2,年产值达20多亿元,占全国养殖面积和产值的50%以上。由于大菱鲆是从欧洲引进的品种,随着在我国养殖时间的延长,抗病力在减弱,发病率一年比一年高,养殖成活率由2001-2004年的90%下降到目前的70%,在     

循环水养殖大菱鲆试验

通过循环水养殖大菱鲆,养殖250 d后大菱鲆平均体重550 g,平均日增重2.3 g,饵料系数1.1。循环水养殖大菱鲆,既能减少环境污染,又能节水、节煤、节电,1000 m2养殖面积能降低生产成本近10万元。     

发挥沿湖资源优势 壮大特种水产产业规模

江苏省扬州市邗江区位于长江北岸,北濒邵伯湖,水资源丰富,水质良好,水产养殖历史悠久,养殖品种丰富多样。2014年,全区水产养殖面积74800×667m2,水产品养殖产量18300t,其中特种水产品产量4500t。全区现已建成4个农业部水产健康养殖示范场、1个省级现代渔业示范园区、1个市级现代渔业产业园区。全区"十三五"规划:至2020年,全区建成以公道省级现代渔业产业园区、湖区高效设施渔业基地、邵伯湖网围健康养殖基地为主体,以区域特色鲜明、科技含量较高、物质装备先进、综合效益显著为目标的特种水产业,特种水产品养殖面积达60000×667m2,特种水产品量产量6000t。     

中国鲆鲽类产品大连地区餐饮消费市场调查

鲆鲽类产业是随着我国自1992年从英国引进大菱鲆,并经过多年努力建立"温室大棚+深海水井"的工厂化养殖模式而发展起来的.环渤海三省一市是鲆鲽类产品的主产地,并向江苏等南部沿海延伸,仅大菱鲆(Scophthalmus maximus)一项,年产量愈5×104 t,年产值超过40亿元[1-2].     

总投资7亿!全国最大海水养殖“渔光互补”工程在浙江宁海投运

正2017年5月28日,全国最大的海水养殖"渔光互补"光伏发电工程正式投运。蛇蟠涂光伏发电工程位于宁海县三门湾现代渔业园区,占地4 200×667 m~2,总装机容量99兆瓦,总投资约7亿元,是省级重点工程。项目按照"渔光互补"的理念规划建设,在确保渔业园区建设的同时,能促进光伏能源开发,有利于充分发挥"土地"的综合效益。     

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 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.     

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).     

Nitrogenous waste excretion and accumulation of urea and ammonia inChalcalburnus tarichi (Cyprinidae), endemic to the extremely alkaline Lake Van (Eastern Turkey)

The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I^–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg^–1 fish·h^–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g^–1·ml^–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min^–1·g^–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min^–1·g^–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.     

Imported ornamental fish are colonized with antibiotic‐resistant bacteria

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.     

Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load

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.     

Influence of the antibacterial herbs, Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia on the survival, growth and bacterial load of Penaeus monodon post larvae

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.