江西主要经济鱼类易发病害调查

通过对江西的南昌、九江、上饶、抚州、宜春、赣州等地区经济鱼类常见病害情况进行为期两年的调查,初步摸清了最近几年江西主要鱼病的种类、流行情况、危害程度.常见经济鱼类易发病害有39种,其中细菌性疾病11种、病毒性鱼病4种、真菌性鱼病2种、寄生虫病16种,营养性及其他疾病6种.一年养殖期内有两个发病高峰期,即5-6月、9-10月.不同水域类型、养殖模式病害程度不同,以池塘精养发病最为严重.探讨了当前江西常见经济鱼类病害发生的主要原因及防治方法,并提出防控建议.     

江西赣北地区大宗淡水鱼类病害调查与分析

对江西赣北地区大宗淡水鱼类养殖、常见病害情况、病原种类、分布及流行规律、发病季节和防治措施进行调查。调查结果表明:根据病原,该地区病害包括四大类:1病毒性;2细菌性;3寄生虫类;4真菌类,以细菌性疾病为主。根据鱼病种类、流行情况、危害程度等,主要常见的鱼类病害有细菌性败血病、细菌性烂鳃和细菌性肠炎,其发病率占鱼病发病率的80.5%。造成疾病高发的原因主要集中在养殖户对鱼类病害防控意识薄弱,亲本、苗种种质退化,养殖水质过肥,池底淤泥过厚等。     

郑州地区鱼类出血病病因与防治技术

鱼类出血病是近几年来广泛流行的一种细菌性传染病,流行面广,发病时间长,死亡率高,1997年,郑州地区有一半以上的高产塘暴发不同程度的出血病,死亡率在10％以上,个别发病严重的池塘,鱼全池死亡。目前,该病已成为制约渔业发展的主要因素之一,如何有效地防治该病的暴发流行已是当务之急。在对郑州地区近万亩养殖水面、十几个养殖场进行鱼病调查和鱼病诊治工作中,针对鱼类出血病的病因和防治对策进行了探索,现总结如下:1 鱼类出血病流行特点及症状     

鱼类细菌性疾病的研究进展

细菌性鱼病是指由各种致病菌引起的鱼类疾病.该类疾病有发病急、传播快、发病率和死亡率高等特点,在微生物引起的鱼类疾病中危害最大,因此,一直受到国内外鱼病研究工作者的关注.近十年来,随着研究手段的提高和技术的发展,该领域的研究日趋深入.本文主要介绍当今细菌性鱼病的种类、诊断技术、病理及防治等方面的进展.……     

福建省主要海水养殖鱼类疾病及其防治

本文通过对福建省沿海海水养殖鱼类发生的疾病种类、主要发病鱼类、疾病主要症状、流行情况及防治方法进行调查，总结出福建省海水养殖鱼类近三年共发生24种疾病，其中病毒性疾病2种，细菌性疾病4种，寄生虫性疾病11种，不明原因疾病7种。这些疾病中危害较大的主要是病毒病、弧菌病和本尼登虫病。     

2005年中国水产养殖病害监测报告(二)

二、鱼类病害(一)病害流行情况2005年4～10月间62种海淡水养殖鱼类发生97种病害(其中病毒性疾病6种、细菌性疾病30种、真菌性疾病2种、寄生虫病害33种、藻类性疾病5种、其它21种及病因不明)。2005年4～10月其间每月的疾病种类在65～97种之间,涉及38～50多个养殖品种。2005年水产养殖鱼类病害以淡水养殖鱼类病害为主。与2004年相比,2005年不仅发病的养殖种类增加,而且疾病种类也增加,发病的种类增加了16个,疾病种类增加了40个。2005年水产养殖鱼类疾病种类中病毒性疾病占6.19%;细菌性疾病占30.93%;寄生虫疾病占24.02%;藻类性疾病占5.15%;真菌…     

治疗淡水鱼类细菌性败血症一例

淡水鱼类细菌性败血症是目前水产养殖业中危害鱼类最多,流行地区最广,发病季节最长,鱼类死亡率最高的传染性鱼病之一.其病原体主要是嗜水气单孢菌、温和气单孢菌、鲁克化耶尔森菌、产碱假单孢菌等多种细菌.2005年6月20日,广东惠州湖基地一养殖户的一口池塘鱼类发生细菌性败血症,经过积极治疗,基本痊愈.现将防治情况小结如下.     

淡水鱼类细菌性败血症的防治

淡水鱼类细菌性败血症的防治淡水鱼类细菌性败血症是近几年来出现的一种新鱼病。笔者着重调查了本县该病的发生、流行情况，初步分析了病因，并采取了行之有效的防治措施。现将情况总结如下：１细菌性败血症的暴发简况１．１发病特征１．１发病鱼类品种：主要危害鲢、鳙、...     

我省夏秋季节常见细菌性鱼病的防治

夏秋两季是鱼类发病的高峰季节。我省夏秋季节常见鱼病有十余种(据“河南省池塘鱼病区系调查”)，其中尤以细菌性鱼病最多，危害最甚。在这些细菌性鱼病中，最常见的(也是危害最大的)有：白头白咀病、烂鳃病、赤皮疾、肠炎病和打印病。因此，夏秋季节做好这些鱼病的防治工作至关重要。     

北方春季细菌性鱼病防治技术措施

正春季是北方地区细菌性鱼病的高发季节,这主要是由于鱼类经过3~6个月越冬过程,为维持身体基础代谢,消耗了大量体内营养物质,体质相对较弱,对细菌性鱼病的抵抗力较差。如果养鱼户不及时进行细菌性鱼病防治,很容易出现问题,造成损失。因此,养殖户要高度重视和加强春季鱼类细菌性鱼病防治工作,以防为主,积极治疗。春季常发生的细菌性鱼病主要有赤皮病、烂鳃病、竖鳞病、肠炎病等。以下介绍常见的细菌性鱼病的防治措施及治疗     

中草药防治寄生性鱼病的概述

通过查阅近年来国内有关中草药防治寄生性鱼病的文献,系统的介绍了常见的寄生性鱼病,并就其中草药防治的研究与应用进行分析。结果显示寄生虫数量达到或超过其危害阈值时,均会构成鱼类病害,危害较大的有斜管虫、双穴吸虫、头槽绦虫、锚头鳋等,控制病原体数量于危害域值之下是鱼病防治的基本策略之一。中草药对寄生性鱼病具有一定的防治作用,加强中草药对寄生性鱼病的研究意义重大。     

北盘江光照水电站建设前后鱼类资源变化

2009年9月和2010年5月,对北盘江光照水电站影响河段鱼类资源进行现场调查,采集鱼类45种,其中18种为新记录种,各河段鱼类组成特点与生态类型相符。结合相关文献资料,确定调查河段鱼类共71种,其中珍稀濒危鱼类4种,珠江水系特有鱼类3种。光照电站的建设对库区河段的鱼类资源影响显著,喜静缓流生境鱼类占76.5%,喜急流...     

Changes in the fish species composition of all Austrian lakes >50 ha during the last 150 years

Abstract  The fish communities of all Austrian natural lakes ( n  = 43) larger than 50 ha in surface area were assessed and the historical fish communities in c . 1850 were reconstructed. During the last 150 years, the fish communities of Austrian lakes have altered: in 49% of lakes at least one indigenous fish species, usually sensitive or small-bodied taxa, is now missing. Conversely, in all but one of the 43 lakes the number of fish species has increased. In particular, certain fish species of interest to angling and commercial fisheries now occur in more lakes. Generalised linear models were used to identify variables that would explain the loss of fish species using categories of lake use (ranking score). The category human population density around the lakes seemed to be one of the main causes for the loss of fish species.     

黄海鱼类感染寄生线虫成虫的初步调查

2005年5月至2006年10月对黄海鱼类寄生线虫感染情况进行了调查,共解剖鱼类93种941尾,采集线虫24 968条,其中成虫923条,隶属于5科5属12种,占所采线虫总数的3.7%。宫脂属线虫为黄海鱼类寄生线虫成虫的优势类群,占所采线虫成虫总数的98.5%。内弯宫脂线虫为黄海鱼类寄生线虫成虫的优势种和广布种。狮子鱼宫脂线虫可能为特有种。     

福建三沙湾鱼卵、仔稚鱼种类组成及其丰度时空分布

根据2008年春季(5月5日、5月17日)和秋季(11月14日、11月30日)分别在三沙湾进行4次鱼卵、仔稚鱼调查资料及历史相关资料,对三沙湾鱼卵、仔稚鱼种类组成、丰度分布的变化进行分析和讨论.结果表明:调查海区出现的鱼卵、仔稚鱼有35种(包括2种未定种类),比1990年和2007年分别增加了9种和12种；其中鱼卵数量...     

珠海桂山风电场水域渔业资源声学评估与空间分布

2019年10月24日至26日,使用便携式Simrad EY60科学探鱼仪对珠海桂山岛海上风电场水域的渔业资源进行了声学调查,研究了该水域的渔业资源组成、数量密度、资源量密度及其空间分布。本次调查共捕获游泳生物和底栖无脊椎动物72种,其中34种参与声学评估。扫海面积法估算的鱼类平均数量密度与资源量密度分别为1.09×10⁴尾/km²,227.48 kg/km²;声学方法估算的鱼类数量密度与资源量密度分别为5.97×10⁵尾/km²,15.13 t/km²。风电场水域鱼类聚集性分布明显,在风电场西北与东南外围水域密度较高,中间水域的密度较低。鱼类单体目标强度（TS）分布范围为-68~-41dB,其中-68~-58 dB的单体TS占主要部分（79.12%）,对应鱼类的体长范围为3~8 cm;随着水深的增加,单体平均TS先减小后增大。本研究是桂山风电场水域渔业资源的首次声学调查,结果较准确地反映了风电场水域多种鱼类的资源量及其分布信息,可为科学评价海上风电场建成运营后对渔业资源的长期影响提供基础数据。     

The global contribution of forage fish to marine fisheries and ecosystems

Forage fish play a pivotal role in marine ecosystems and economies worldwide by sustaining many predators and fisheries directly and indirectly. We estimate global forage fish contributions to marine ecosystems through a synthesis of 72 published Ecopath models from around the world. Three distinct contributions of forage fish were examined: (i) the ecological support service of forage fish to predators in marine ecosystems, (ii) the total catch and value of forage fisheries and (iii) the support service of forage fish to the catch and value of other commercially targeted predators. Forage fish use and value varied and exhibited patterns across latitudes and ecosystem types. Forage fish supported many kinds of predators, including fish, seabirds, marine mammals and squid. Overall, forage fish contribute a total of about $16.9 billion USD to global fisheries values annually, i.e. 20% of the global ex‐vessel catch values of all marine fisheries combined. While the global catch value of forage fisheries was $5.6 billion, fisheries supported by forage fish were more than twice as valuable ($11.3 billion). These estimates provide important information for evaluating the trade‐offs of various uses of forage fish across ecosystem types, latitudes and globally. We did not estimate a monetary value for supportive contributions of forage fish to recreational fisheries or to uses unrelated to fisheries, and thus the estimates of economic value reported herein understate the global value of forage fishes.     

Fishing for feed in China: Facts,impacts and implications

China is the world's largest capture fisheries and aquaculture producer. Over recent decades, China's domestic marine catch composition has changed markedly, from large volumes of a few high‐valued food species to multiple, small, low‐valued, species, a significant proportion of which is primarily used as animal, especially fish, feed. Despite the growing volume and economic importance of the feed catches, their species composition, catch volumes and socio‐environmental impacts are all poorly understood. Based on a nationwide survey of >800 fishing vessels, and the identification and measurement of >12,000 fish and invertebrate individuals, the present study provides an overview of the feed component of China's domestic marine catch, by volumes, species and sizes, and found it to be substantial and biologically unsustainable. Half of the trawler catch (3 million metric tons, mmt), or 35% of the total catch (4.6 mmt) in China's exclusive economic zone, are now comprised of low‐valued “feed‐grade fish”. The present study identified 218 fish species, 50 crustaceans and five cephalopods, and of these, 102 fish species were food species with 89% individuals in their juvenile size ranges. Feed‐grade fish were mainly used as aquaculture feed directly, or indirectly, through the feed industry after reduction to fishmeal and fish oil. The unparalleled scale and poor fisheries resource condition of China's domestic marine fisheries, in parallel with severe overfishing of juveniles, creates a demand for fundamental changes to fishery management practices, including a significant reduction of fishing effort to ensure productivity and ecosystem resilience.     

养殖鱼康鱼良白鱼常见病害防治技术

鱼康鱼良白鱼人工育种和驯化的成功,奠定了其养殖业的发展基础。近年来,随着养殖技术的不断发展,池塘养殖鱼康鱼良白鱼得到了快速的推广和发展。然而,随着集约化养殖程度的提高和养殖密度的增加,养殖鱼康鱼良白鱼的病害逐渐增多,呈现出寄生虫病增多,多病原、多病种同时发生,流行时间长,危害重的趋势。文章根据养殖实践,总结介绍了鱼康鱼良白鱼养殖过程中出现的真菌病、寄生虫病、细菌病及其主要症状、流行情况和防治方法。     

A review of mycobacteriosis in marine fish

Mycobacteriosis is a serious and often lethal disease of fish, affecting a wide range of species globally both in culture and wild settings. Caused by several species of the genus Mycobacterium , the disease has received considerable attention in recent years because of the discovery of new species in piscine hosts, epizootics in wild fisheries, and the ability of a few species to infect humans. The impact of this disease in aquaculture and the aquaria trade has been well reported and there is currently no widely accepted cure other than depopulation and facility disinfection. However, the impact on wild fisheries is poorly understood and may relate to species-specific interactions (host–pathogen) and possibly environmental stressors. In this review, much of what is known about mycobacteriosis in marine fish is summarized with particular attention to an epizootic in striped bass, Morone saxatilis , (Walbaum), in Chesapeake Bay, USA.