蛙病的诊断与防治技术

十、肿腿病▲病因：该病因皮肤擦伤后受细菌感染所致。▲症状：病蛙后腿肿胀，皮下积水，有时表皮充血发红，有明显炎症，跳跃无力，厌食，最后死亡。▲流行及危害：发病的多数为种蛙，常在从外地引种入池后几天内发病。蛙在越冬苏醒后易发病，该病有一定的传染性。▲诊断...     

常见甲鱼病及其防治（中）

四、红底板病（又称赤斑病,红斑病、腹甲红肿病） 1.病原体症状及病因 就目前研究的结果,认为红底板病有两种病因：一种是由红脖子病引发的症状,另一种是由点状产气单胞菌点状亚种引起的症状。在这里,从病原来讲,是针对后一种病因而谈。     

暗纹东方鲀常见病的防治

我们在暗纹东方的工厂化养殖过程中,发现其较易感染小瓜虫病、刺激隐鞭虫病及肠炎、烂鳃、营养不良等症,对上述疾病的病因、症状及防治方法做如下介绍,供广大养殖工作者参考。1小瓜虫病病因小瓜虫寄生引起。症状肉眼可见鳃、鳍、体表布满白点状囊孢,镜检虫体呈椭圆形,有纤毛,中间有“马蹄形”核。治疗方法(1)百虫净全池泼洒,使用浓度为0.15克/米3,效果显著。(2)用硫酸铜、硫酸亚铁(5∶2)混合溶液0.7克/米3全池泼洒,效果显著。2指环虫病病因指环虫寄生在鱼的鳃丝上而引发此病。症状鱼鳃丝粘液增多,全部或部分呈苍白色,呼吸困难,游动缓慢。治…     

对虾暴发性疾病及防治对策

本文根据几年来虾病研究工作的进展和江苏对虾流行病学调查结果，总结分析了病因及病原学方面的有关问题，并针对水温、气候、密度等诱发因子，从生态角度提出了虾病防治方法及措施。     

鳖常见疾病及防治技术

鳖常见疾病及防治技术鳖在天然条件下．由于生态环境较好．种群密度较小，自身的抵抗力较强，一般患病较少。但近年来，随着集约化高密度养鳖，鳖病已成为阻碍其发展的一大障碍，造成了很大的经济损失。笔者根据实践以及调查研究，初步找出了鳖常见疾病的病因及防治方法，...     

鳜鱼养殖病害防治技术

一、鳜鱼养殖病害及防治1郾纤毛虫病(车轮虫、斜管虫、舌杯虫病)病因是由车轮虫、斜管虫、舌杯虫等寄生虫引起。具体症状表现为病鱼浮头靠近池岸,游动缓慢,口张开,体表呈灰白色,鳃丝呈灰白色、粘液多,并发烂鳃病,病重时鱼体失去平衡,上下浮动,最后导致死亡。此病在鱼种阶段危害     

人工养殖鲍鱼常见疾病防治技术

鲍鱼是一种具有很高经济价值的贝类,以味道鲜美、营养价值高而著称,又因其自然资源量低,故而更成为珍稀食品。在我国,鲍鱼的养殖在上世纪90年代飞速发展,是继海带、紫菜、贻贝、扇贝、对虾之后的又一重要的新兴海水养殖品种。随着鲍鱼养殖规模的不断扩大,其病害也相继发生,并且有逐年加重之势。目前,病害问题已对我国养鲍业的发展构成了严重威胁。本文将鲍鱼人工养殖中常见的几种疾病的病因、症状、诊断以及防治措施作一总结介绍,供养殖者借鉴。一、肌肉萎缩症【病因及流行情况】该病由病毒感染而致,因直接从贝足组织肌肉萎缩坏死,而命名为…     

鱼类营养代谢病

营养代谢病包括新陈代谢障碍病和营养缺乏病。综述了几种常见的鱼类营养代谢病，如鱼类的脂肪肝病、营养性障碍综合症、胆囊结石症、鲤鱼出血病、罗非鱼越冬障碍症等的病因、发病机理、病鱼症状以及防治措施。     

胡子鲶“黑体病”的防治

一、病因及症状胡子鲶“黑体病”是一种细菌性传染病,与饲料及水体污染有密切关系。投喂霉变饲料,或带病菌水体流入传播精原都会直接引起病发。长其投喂单一饲料,或时饥时饱,导致胡子鲶消化系统失调,降低抗病能力也会发生“黑体病”。患病鱼体主要症状是体色变黑,胸鳍基部红肿,有的头北部出现霉斑点、鳍条溃烂、肛门红肿、腹腔积水等症状。此病传染快,患病鱼类食欲显著下降,常悬垂于表层水体,最后死亡。死亡率可达80％以上。     

1992年福建省虾病症状,流行特点,病因分析及其对策

八十年代以来,国内外出现一股养虾业,目前这股势头正方兴未艾。但是,在长期养虾过程中,面临棘手问题,就是流行性暴发虾病,这个问题的研究已引起虾病专家们的重视和兴趣。作者对福建省1992年虾病症状、流行特点、病因分析及其对策作了详细的概述。编者认为,该论文的发表,对1993年暴发性虾病的病因的分析及其防治对策具有重要的参考价值。     

龙江入海口水域氮、磷含量变化及富营养化评价

根据2012—2013年龙江入海口水域的水质调查数据,对该水域氮、磷营养盐分布状况、结构特征及富营养评价进行了研究。结果表明,2012年和2013年DIN含量范围分别为0.808~5.285、0.610~5.383 mg/L,PO4-P含量范围分别为0.028~0.324、0.096~0.643mg/L,呈不同程度的超标状态并有上升趋势。受海水稀释作用,营养盐浓度由河口向外逐渐降低;受枯水期地表径流减少导致营养盐浓缩的影响,营养盐含量呈现冬、春季高,夏、秋季低的季节性变化;NH4-N在DIN中的占比在51.15%~63.25%和43.88%~69.39%之间,DIN的污染程度主要受NH4-N控制。营养盐结构上N/P比值范围为10.83~13.12,接近适合浮游植物生长繁殖的Redfield比值(16∶1),潜在性富营养化程度评价分析表明该水域处于富营养化状态,N、P营养盐绝对浓度高,可能有赤潮等严重海洋生态问题发生的潜在风险。     

淇河鲫与野生鲫形态及染色体差异研究

对淇河鲫和普通野生鲫的传统形态学性状和框架性状进行了统计学比较研究,并对其染色体数量进行了检测.试验结果表明,(1)淇河鲫为三倍体,3n=156±,野生鲫为二倍体,2n=100±.(2)淇河鲫在体高、体厚等方面显著大于野生鲫,符合"双倍鲫"的形态特征,且侧线鳞数也多于野生鲫;而野生鲫在头长、尾高方面占优.(3)淇河鲫相对怀卵量显著高于野生鲫,而相对肠长显著低于野生鲫,这与淇河鲫长期处于人工饲养条件有关.     

Overwintering Paddlefish in Monoculture and in Polyculture with Channel Catfish and Rainbow Trout

Paddlefish, "Polydon spathula," overwintered in monoculture and in polyculture with fingerling channel catfish, "Ictalurus punctatus," or with rainbow trout, "Oncorhynchus mykiss," were examined for growth and compatibility in nine 0.04-ha ponds. Paddlefish in polyculture had significantly greater (P ≤ 0.05) individual weight gains than those in monoculture. Feed in polyculture treatments probably served as a fertilizer, promoting zooplankton production for paddlefish consumption and growth. Paddlefish in polyculture with fingerling channel catfish had significantly greater (P < 0.05) individual weight gains than paddlefish polycultured with rainbow trout, although there was less feed input with channel catfish than with rainbow trout. Bloody and frayed fins on paddlefish stocked with rainbow trout suggested fin nipping by rainbow trout which may have interfered with paddlefish feeding and growth. Paddlefish overwintered in polyculture with fingerling channel catfish demonstrated increased weight gains and good species compatibility.     

主要养殖鲑科鱼类遗传育种的研究进展

冷水性鲑科鱼类肉质鲜美,高蛋白、高不饱和脂肪酸、营养丰富、无肌间刺、易加工,是世界性养殖鱼类,其中大西洋鲑、虹鳟和红点鲑属鱼类等主要养殖鲑科鱼类,一直是水产遗传育种领域的重要研究对象。本文简要叙述了鲑科鱼类遗传育种研究的历史和现状,主要介绍了经济性状遗传参数估计、选择育种、分子遗传与标记辅助育种等方面的研究进展,提出了我国鲑科鱼类遗传育种工作重点研究的方向。     

黄海北部春季和夏季浮游动物生态特性与时空分布

根据2015年3月(春季)和6月(夏季)对黄海北部辽宁近岸海域的浮游动物调查结果,分析了两个季节的浮游动物种类、生物量、丰度等群落结构特征。此次调查共鉴定出浮游动物47种,其中春季42种,夏季34种。浮游动物以浮游幼虫和小型桡足类为主。桡足类幼虫、棘皮动物幼体、桡足类幼体、洪氏纺锤水蚤、短角长腹剑水蚤、小拟哲水蚤、拟长腹剑水蚤和腹针胸刺水蚤为春季优势种;夏季浮游动物优势种依次为桡足类幼体、洪氏纺锤水蚤,拟长腹剑水蚤、短角长腹剑水蚤、桡足类幼虫、小拟哲水蚤和腹针胸刺水蚤。春季浮游动物平均生物量为512.09mg/m~3,平均丰度为15 522.18个/m~3;夏季浮游动物平均生物量为218.84mg/m~3,平均丰度为7582.39个/m~3;浮游动物生物量和丰度均为春季较高。黄海北部辽宁沿岸海域的浮游动物生物量、丰度较高。水温是影响浮游动物群落结构的重要环境因子。     

渔业通信管理存在的问题及对策

随着中国改革开放的深入,海洋渔业捕捞的发展正走上正规化,从而使得沿海地区水上安全通信在保障海上生产安全、促进海洋渔业经济稳定发展中的作用越来越重要,特别是近两年来,由政府资助为渔民统一购置安装单边带电台,使渔业无线电通信真正成为"信息交流的桥梁"、"安全生产的耳目"、"科技服务的窗口",是海洋渔业不可替代的通信方式.但随之而来的的问题和矛盾也逐渐显露并严重制约着渔业无线电通信管理事业的健康发展.作为渔业通信管理工作者,如何加强渔业通信网络建设,不断提高为渔民生产服务的质量,确保渔民生命财产安全,成为当前义不容辞的责任.下面结合当前渔业通信管理工作的现状,谈一谈渔业通信管理工作中存在的问题及解决措施.     

Parasitic diseases in sheep and goats in Germany

A review is presented on the species spectrum, biology and epidemiology of endo- and ectoparasites of sheep and goats in Germany. Current therapeutic, prophylactic and metaphylactic measures are given and discussed.     

Examining changes in participation in recreational fisheries in England and Wales

Abstract Inland fisheries in England and Wales have high economic and social values. Managing participation to maximise fishery performance is key to maintaining this status. The capital value of fishing rights for migratory salmonid fisheries is €165 million. Coarse fisheries contribute €1030 million to the economy. The central tenet to increasing participation in recreational salmonid fisheries is that an increase in stock size will result in more anglers accessing the fishery. This was examined for salmon on the rivers Usk and Lune where exploitation restrictions increased the number of salmon available to anglers. On the River Lune, the number of salmon available post‐intervention increased by 66%. There was no significant increase in catch while the number of anglers decreased by 16.3%. On the River Usk, the closure of the net fishery potentially resulted in an additional ～1200 salmon being available. Following closure, there was no significant change in rod catch or in the number of anglers. Increased participation is dependent less upon stock manipulation for coarse fisheries and more upon facilitating the activity. In recent years, urban fishery development programmes have provided improved access to local fishing opportunity. Also, new anglers have been targeted through campaigns such as Get Hooked on Fishing and the Scout Angler Badge.     

Advances and challenges in marine conservation in Chile: A regional and global comparison

1. Despite significant progress made in Chile, and globally, in establishing marine protected areas (MPAs), the actual contribution to marine biodiversity conservation needs to be revised, to focus on representativeness and the diversity of tools alongside effective implementation, management, and enforcement.
2. This study makes progress in this direction, describing the most recent advances in marine conservation in Chile and analysing the contribution of the different conservation instruments as well as the distribution of designated areas across ecoregions. Furthermore, it examines the potential contribution of alternative area-based instruments to balance ocean protection. The advances observed in Chile were compared among four South American countries and five leading countries in ocean conservation, analysing protection levels in coastal areas, continental exclusive economic zones, and overseas territories.
3. Data on MPA boundaries and attributes were sourced from the World Database on Protected Areas and complemented the official information on MPAs and territorial user rights for fisheries and for indigenous people in South America.
4. The current level of protection in Chile is among the highest in the world in area coverage and in the proportion of the continental exclusive economic zone assigned to fully protected areas. However, it exhibits the strongest imbalances in the distribution of designated MPAs between coastal and oceanic waters, in comparison with the leading countries and also within South America (Perú, Chile, Argentina, and Uruguay), and among ecoregions.
5. The patterns observed suggest that Chile has advanced, but concentrated, conservation efforts in low-threat, remote ecoregions. There is an urgent need to progress towards high-threat ecoregions, which implies balancing the needs of nature and people. The distribution of ancillary conservation instruments can help double the level of protection in threatened coastal areas, filling gaps in marine conservation and creating an opportunity to progress and diversify conservation strategies.