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1.
红水河岩滩水库鱼类资源声学评估 总被引：1，自引：0，他引：1
为评估梯级开发下渔业资源变化情况,2015年9月采用分裂波束鱼探仪EY60(120 kHz,250 W)对红水河岩滩水库库区及上游江段鱼类资源进行声学调查,并结合渔获物统计和地理统计分析对鱼类时空分布进行分析,评估鱼类资源量。结果显示整个调查区域的鱼类资源密度为(0.53±2.11)尾·m~(-2)(±SD),从水坝上游至库区呈增长趋势,鱼类资源密度水平分布与水深无显著相关关系。垂直分布方面,鱼类主要分布在30 m以内水层;不同大小个体对水深有一定的选择性,小个体鱼类(10 cm)约86.2%分布在30 m水层之内;大个体(30 cm)有44.7%分布在40 m以下水层。基于鱼类分布GIS建模,估算调查区域鱼类资源量为6.57×10~7尾。 相似文献
2.
用水声学评估水库鱼类资源增殖放流的效果 总被引：1，自引：0，他引：1
合理开展水库鱼类增殖放流,可提高水库鱼产力、修复水库生态环境和防治水库富营养化等,对水库健康运行具有重要意义。而科学评估水库鱼类资源动态及增殖放流净化效果将为合理开展增殖放流提供基础和指导。本研究于2015年运用BioSonics DT-X科学回声探测仪(208kHz)在老虎潭水库增殖放流完成后(夏季)和渔获期(冬季)对其鱼类资源进行走航式水声学调查。结合渔获物调查,对老虎潭水库的鱼类大小组成、空间分布、密度和资源量等进行测定,评估增殖放流活动对水体的净化效果。结果显示,夏季鱼类的平均目标强度为(-51.76±3.37)dB,冬季为(-45.058±4.26)dB,夏季和冬季鱼类目标回声强度大小存在显著性差异(P0.001)。夏冬两季鱼类密度的垂直分布存在显著性差异(P0.001)。老虎潭水库库区夏季鱼类的总尾数为1.297×10~6尾,资源量约10 246kg。冬季鱼类的总尾数为4.8×10~5尾,资源量约43 085kg。增殖放流后鱼类资源量增长明显,达32 839kg,共转移出碳、氮、磷的净含量分别为3.379×10~3、1.031×10~3、1.81×10~2 kg,实现了对水体营养物质的转移。后续研究可关注每年渔获量的科学设置,合理利用鱼类资源并有效降低库区水体营养水平。 相似文献
3.
北盘江董箐水电站库区鱼类资源调查 总被引：1，自引：0，他引：1
为探究董箐水电站成库后库区内渔业资源群落组成和物种多样性变化情况,给董箐水库资源的合理开发与利用、库区鱼类资源保护以及增殖放流活动提供技术参考和科学依据,于2013-2015年在董箐库区进行6次生物采样和走访调查。结果表明,本次调查共采集渔获物668尾,隶属3目、8科、29属、39种,其中鲤科鱼类最多,占总种类数的60.8%;唇鲮(Semilabeo notabilis)、花鱼骨(Hemibarbus maculatus)、鲤(Cyprinus carpio)、鲫(Carassius auratus)、云南光唇鱼(Acrossocheilus yunnanensis)、光倒刺鲃(Spinibarbus hollandi)、黄颡鱼(Pelteobagrus fulvidracoi)为库区的优势种;董箐库区鱼类群落生物多样性采用Margalef丰富度指数(DMa)、Shannon-Wiener多样性指数(H')和Pielou均匀度指数(J')作为评价指标,其平均值为3.811、0.914和2.649,分析发现鱼类物种多样性呈减少趋势。对比历史资料发现,库区鱼类群落结构已发生改变,喜静水或缓流生境的鱼类逐渐成为库区优势种群;由于生态环境的改变,原河段流水型鱼类逐渐被替代,数量逐渐减少。 相似文献
4.
三峡水库成库期间鱼类空间分布的水声学研究 总被引：2，自引：0，他引：2
2007年4月18日～5月1日,利用SIMRAD EY60回声探测仪(又称鱼探仪)对三峡水库坝前到丰都干流以及9条主要支流进行了水声学探测.采用垂直探测结合"之"字形路线的方法对库区整个水体鱼类的分布状况进行了研究.调查水域长度约有600 km,回波数据分成1 232个片段进行分析.结果表明:在5m以下水层,体长大于6cm的鱼类在该区域平均密度为567.68尾/dam3,且鱼类分布不均匀.在巫山至奉节江段鱼类的密度最低,密度的平均值和标准误(mean±S.E)为(8.1±0.47)尾/dam3;在忠县到丰都江段密度最高,平均值和标准误(mean±S.E)为(2597.06±154.08)尾/dam3.从坝前到丰都,干流鱼类资源量总体上呈现逐步增加的趋势.支流资源量要比干流高.目标强度在-60～-50 dB的鱼体大小差异不显著,大于-50dB鱼体的平均目标强度在巴东-巫山江段最高,巫山-奉节江段及抱龙河次之.小型鱼体的大小在各江段没有统计学差异,中型和大型鱼体在巴东-巫山江段鱼体个体相对最大,万州-忠县江段以及小江、长滩河等水域鱼类个体相对较小. 相似文献
5.
为了解北京地区密云水库鱼类资源及空间分布特征,对库区的主要渔获物及鱼类大小组成、密度及空间分布特征进行了探测评估分析。结果表明:密云水库主要渔获物为鲢、鳙、鲤、鲫、戴氏红鲌、团头鲂、草鱼、鯵条和池沼公鱼等,其中鲢和鳙分别占总渔获量的52.7 %和37.8 %。回声探测结果显示,鱼类平均目标强度为(-46.8±7.6)dB,鱼类体长范围为3.0~74.1 cm,平均体长为10.15 cm。不同水域鱼类密度空间分布有极显著性差异(P＜0.01),鱼类密度最大值出现在水库中心水域,为865.20 ind./1 000 m3,鱼类密度最小值位于内湖水域,仅为2.87 ind./1 000 m3。不同水层间鱼类密度空间分布亦极不均匀(P＜0.01),大部分鱼类倾向于分布在水体中层,鱼类密度为570.66 ind./1 000 m3。 相似文献
6.
为了解荆江航道整治工程中透水框架的集鱼效果,分别于2014年5-6月和2015年5-6月,采用科学探鱼仪SIMRAD EY60和双频识别声纳(DIDSON)ARIS EXPORER 1800两种水声学设备,分别对荆江瓦口子水道的金城洲和太平口水道的腊林洲透水框架水域的鱼类分布情况进行了水声学监测,并对工程江段的鱼类进行了刺网调查。结果显示:采用刺网捕获鱼类17种共204尾,其中数量和重量最多的都是鳊鱼,分别占64.71%和39.62%。渔获物体长范围是10~80 cm,平均体长是(26.90±8.82)cm;EY60监测到腊林洲工程区鱼的数目是金城洲工程区的1.92倍,DIDSON监测腊林洲工程区鱼的数目是金城洲工程区的2.36倍;EY60监测到金城洲鱼类体长集中在5~10 cm,占55.24%,腊林洲鱼类体长集中在30~50 cm,占45.38%。结果表明,透水框架群对于鱼类具有一定的诱集效果。 相似文献
7.
2018年9月25日至2018年11月15日对乌苏里江抚远抓吉江段和饶河四排江段的经济鱼类进行了资源调查。采用三层流刺网(10 cm网眼)共作业86网次(其中:抓吉作业19网次;四排作业67网次),定置网(5 cm网眼)作业3 d。共获得渔获物2 309尾,重量为342 587 g,平均体重为148.4 g/尾。其中:定置网(5 cm网眼)共获得渔获物2 082尾,重量为52 312 g,平均体重为25.1 g/尾;三层流刺网(10 cm网眼)共获得渔获物227尾,重量为290 275 g,平均体重为1 278.7 g/尾。其中抓吉上滩捕获鱼类66尾,重量为135 900 g,平均体重为2 059.1 g/尾;四排捕获鱼类161尾,重量为154 375 g,平均体重为958.9 g/尾。总的渔获率为1.32尾/km,单位捕捞努力量渔获量为1 687.6 g/km。两个捕捞滩地的渔获率和单位捕捞努力量分别为:抓吉渔获率1.74尾/km,单位捕捞努力量3 576.3 g/km;四排渔获率1.20尾/km,单位捕捞努力量1 152.1 g/km。本次调查到乌苏里江鱼类共28种,隶属9科25属。其中:鲤科16种,占57.1%;鲑科4种,占14.3%;鲿科2种,占7.1%;茴鱼科、狗鱼科、鳕科、鮨科、鲇科和鲟科各1种,各占3.6%,其中冷水性鱼类7种,占比为25%。 相似文献
8.
9.
2018年8月15-19日,利用Lowrance elite-7 Ti回声探测仪首次对云南省泸沽湖展开鱼类空间分布及资源量评估。调查采用"之"字形航线对泸沽湖全湖进行水声学探测,累计航程42.71 km,基于深度变化值将探测水体分为若干探测单元进行鱼类资源评估,并运用反距离插值法(IDW)基于各单元密度绘制进行空间分布图。水声学探测结果表明,泸沽湖鱼类空间分布不均匀,水平方向上,鱼类主要集群分布于近岸环形水域,其中小渔坝附近水域鱼类密度最高,湖心区域鱼类密度最低;垂直方向上,鱼类在表层水域分布较为集中;2018年8月泸沽湖鱼类密度为0.153尾·(1000 m^3)^-1,数量24.39万尾,总资源量50.55 t;其中,鲫(Carassius auratus)21.17万尾、17.36 t,鲤(Cyprinus carpio)1.74万尾、23.01 t,草鱼(Ctenopharyngodon idellus)8.63万尾、8.63 t,大鳞副泥鳅(Paramisgurnus dabryanus)0.68万尾、1.33 t,小口裂腹鱼(Schizothorax microstomus)0.07万尾、0.22 t。此次调查未发现曾出现记录的宁蒗裂腹鱼(S.ninglangensis)和厚唇裂腹鱼(S.labrosus)。 相似文献
10.
为了解库区建设对鱼类生物多样性的影响,掌握董箐库区内渔业资源群落组成和物种多样性变化情况。2013年--2015年在董箐库区进行6次生物采样和走访调查,采集渔获物共668尾,隶属3目8科29属39种,鲤科鱼类最多,占总数的60.8%;群落以杂食性鱼类和喜静缓流生态类型鱼类为主,唇鲮(Semilabeo notabilis)、花鱼骨(Hemibarbus maculatus)、鲤鱼(Cyprinus carpio)、鲫鱼(Carassius auratus)、云南光唇鱼(Acrossocheilus yunnanensis)、光倒刺鲃(S.hollandi)、黄颡鱼(Pelteobagrus fulvidracoi)为库区的优势种,对比历史资料发现库区鱼类群落结构已发生改变;董箐库区鱼类群落生物多样性采用Margalef 丰富度指数、Shannon-wiener多样性指数()、Pielou均匀度指数()、Wilhm改进指数()作为评价指标,各指标的平均值为3.811、0.914、2.649、2.529,分析数据发现鱼类生物多样性也有衰减。 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
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13.
Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
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. 相似文献
14.
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
15.
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
16.
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. 相似文献
17.
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
18.
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
19.
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