淡水养殖鱼类常见鳃病的诊断及防治

鱼生活在水中,靠鳃吸入水中的溶解氧,水中存在的病原体很容易感染到鳃上,鳃的发病率很高,当鱼鳃患病影响鱼类的正常呼吸,鱼体会通过自身调节提高呼吸运动节律来弥补病鳃气体交换的不足,当鳃的气体交换量(即呼出二氧化碳,吸收水中氧气)降低到不能维     

鱼类鳃病及其防治技术

鱼类鳃病,按其致病病原体可分为细菌性烂鳃病、真菌性烂鳃病(又称鳃霉病)、寄生虫性鳃病。 细菌性烂鳃病是常见的传染性鱼病,常与细菌性肠炎病、赤皮病并发,严重危害草鱼鱼种、成鱼,一旦暴发,草鱼死亡率高达60％以上,同时也严重威胁青鱼、鲢鱼和鳙鱼。近年来随着高密度、集约化养殖方式的迅     

池塘养鱼常见鳃病的防治

鱼类生活在水中，主要的呼吸器官是适应水中呼吸的鳃，水中存在的大量病原生物很容易感染到鳃上。鳃的发病率很高，因此有“养鱼先养水，治病先治鳃”之说。鱼的鳃病种类很多，为了准确诊断、合理用药，将鳃病分为以下五大类型：     

池塘精养鱼常见鳃病的防治

鱼生活在水中,靠鳃吸入水中的溶解氧,水中存在的大量病原体生物很容易感染到鳃上。鳃的发病率很高,因此有“养鱼先养水,治病先治鳃”之说,这在精养鱼塘显得尤为重要。鱼的鳃病种类很多,为了准确诊断,合理用药,将鳃病分为以下六大类型:     

精养池塘鱼类常见鳃病的防治方法

鱼生活在水中,靠鳃吸入水中的溶解氧,水中存在的大量病原体生物很容易感染到鳃上。鳃的发病率很高,因此有“养鱼先养水,治病先治鳃”之说。鱼的鳃病种类很多,为了准确诊断、合理用药,笔者凭着多年从事水产工作的经验,将鳃病分为以下6大类,以期为水产业同行提供借鉴和参考。1　营养性鳃病1 1　症状鳃丝弯曲,鳃小片曲屈、萎缩,排列不整齐。1 2　病因由于饲料中缺乏泛酸或其它营养不平衡引起,使鱼体免疫能力下降,易引起细菌感染,寄生虫侵入。1 3　防治方法合理调配精饲料,做到氨基酸、不饱和脂肪酸、钙、磷、维生素和微量元素及多项营养指…     

几种鳃病的成因及诊断与防治

鱼类鳃病，或细菌感染，或真菌感染，或被寄生虫侵袭复被细菌感染，其诊断可通过目测、镜检等手段确定病因，依据检测结果，针对不同的病原体，采用相对的杀虫杀菌方法，即可得到有效的治疗。细菌、真菌性鳃病，只需用杀菌药物，按使用说明书标示的用法、用量进行治疗；被寄生虫侵袭继发细菌感染，则采用先杀虫（如甲壳类用菊脂类杀虫剂液，蠕虫类用有机磷杀虫剂，原生动物用重金属盐类）后杀菌，或杀虫杀菌同时进行，这在生产中，已为人们熟识并得到广泛运用。 对于水质恶化、水中有害物质引起中毒，过量滥施药物及鱼类肝脾病诱发的鳃病，…     

大河水产专栏

精养池淡水鱼类的鳃病分析贾滔 汤红梅1.由水质恶化引起的鳃病高产池塘水质污染严重,当水中氨含量长期超标,在分子氨的刺激下,鳃分泌大量粘液,鳃丝呈紫红色,鳃丝的边缘呈白色。因鳃片表面复盖大量粘液严重影响了气体交换。在炎热的夏季水温较高的时候,病鱼常浮于水面,摄食减少,生长缓慢。目检病鱼的鳃无细菌性烂鳃病症状;镜检一般无寄生虫或寄生虫很少,如再配合水质监测,水中氨氮含量超标,可以确诊为由水质恶化引起的鳃病。防治方法:应积极采取换水,增氧等措施降低水中的氨含量。如果将水中的氨含量降低到鱼类能长期忍受的最高氨浓度0.025mg/L以下,就不会对鱼类产生危害。换水不便的池塘也可泼洒西菲利、科利尔等生物调水剂,达到快速降低氨氮的目的。且勿大量施用生石灰等碱性物质,以免将氨瞬时转化为亚硝酸盐加强了对鱼的毒害。     

室内循环水养殖系统内草鱼鱼种烂鳃病的防治案例分析

正草鱼是世界上产量最高的养殖鱼类。我国草鱼养殖历史悠久,养殖技术较为成熟。草鱼养殖过程中,病害较多,春末夏初一般是"老三病"(烂鳃病、肠炎病、赤皮病并发症)的高发季节。根据烂鳃病发病原因可分寄生虫性、真菌性和细菌性三种。寄生虫性烂鳃病例进行镜检时,可发现车轮虫、指环虫、三代虫或黏孢子虫等常见寄生虫;而真菌性烂鳃病例的镜检则会发现鳃霉菌丝;细菌性烂鳃病病原包括鱼害黏球菌等。目     

鱼类两种鳃病的诊治

在鱼类养殖生产中，鳃部疾病是危害最严重鱼病之一。因而，对鱼类鳃病的诊断是否准确，是否及时地对症下药，直接关系着养殖效益。笔者根据多年诊治鱼病的实践，对鱼类由寄生虫和细菌引起的鳃病的诊治作一小结。 一、两种鳃病的共同特征 由寄生虫和细菌引起的鳃病的发病部位均在鱼类的鳃丝上，并且鳃丝均会出现缺损、糜烂、充血、水肿等症状，病鱼吃食量明显下降，身体逐渐消瘦，多漂浮在水面或无规律地沉浮。特别是放养的鱼类还没有长至商品鱼规格，在初夏会频繁出现浮头现象，开动增氧机后鱼仍不下水。 二、两种鳃病的区别 （一）由寄生虫…     

鱼类几种烂鳃病的应对措施

鳃是鱼类重要的呼吸器官,由鳃弓、鳃耙和鳃丝组成.鳃丝组织分布许多毛细血管,水中溶氧通过鳃丝表皮细胞渗透进入血液达到气体交换.鲢鳙等滤食性鱼类通过鳃耙将水体浮游生物过滤进入食道而摄食.同时鳃具有调节体内渗透压作用,可以将过量氨氮等机体代谢产物经鳃器官排泄到体外,如果鳃组织发生病变,将直接破坏呼吸功能,威胁鱼类的生存.所以,在水产养殖过程中及时预防和治疗鳃病显得尤为重要.根据笔者多年生产实践总结,将鱼类烂鳃病的分类及应对措施介绍如下,供水产同仁参考. 1 寄生性烂鳃 1.1 流行季节 流行时间为每年4-9月. 1.2 主要症状 病鱼鱼体发黑,尾柄灰白,鳃盖张开难以闭合,鳃丝发白并参差不齐,鳃片表面黏液增多,鳃片腐烂,镜检可见大量寄生虫如:中华鳋、锚头鳋、指环虫、三代虫、车轮虫、孢子虫等. 1.3 防治方法     

Estimation of variation of virulence of Renibacterium salmoninarum by survival analysis of experimental infection of salmonid fish

The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms.     

母猪胎衣不下的病因与防治要点

猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。     

水硬度对七彩神仙鱼幼鱼发育的影响

采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。     

虎斑乌贼受精卵卵黄营养成分分析

本实验对虎斑乌贼受精卵卵黄的营养成分进行分析,旨在探讨其幼体的营养需求量,为其幼体配合饲料研制提供参考数据。随机选取大约800个虎斑乌贼受精卵的卵黄,采用国家标准方法测定其水分、灰分、粗蛋白质、粗脂肪、氨基酸、脂肪酸和矿物元素含量。结果表明:1)虎斑乌贼受精卵卵黄中粗蛋白质含量为76.33%(干重基础);总氨基酸(TAA)和必需氨基酸(EAA)含量分别为71.22%和32.38%(干重基础),EAA/TAA为45.46%,氨基酸中以谷氨酸(Glu)含量最高(9.97%),必需氨基酸中亮氨酸(Leu)含量最高(7.58%)。2)其粗脂肪含量12.71%(干重基础);共检出17种脂肪酸,包括8种饱和脂肪酸(SFA)、5种单不饱和脂肪酸(MUFA)和4种多不饱和脂肪酸(PUFA),SFA、MUFA和PUFA分别占脂肪酸总量的43.47%、7.54%和49.25%,其中以DHA含量最高,达32.80%,EPA含量为7.70%,DHA/EPA为4.26。3)检测出Na、K、Ca、Mg、Sr、Mn、Fe、Cu、Zn、Al和As 矿物元素,微量元素中富含Zn、Al和Fe,含量分别为 0.77、0.71和0.43 mg/kg(鲜重基础)。由此可见,卵黄具有高蛋白、低脂肪,富含n-3PUFA的特点;虎斑乌贼幼体饲料中蛋白质需求量参考值为76.33%;氨基酸需求量参考值,如赖氨酸(Lys)为5.49%,蛋氨酸(Met)为2.63%;脂肪的需求量参考值为12.71%,DHA为4.17%,EPA为0.98%;微量元素需求量参考值,如Zn为2.77 mg/kg,Cu为0.19 mg/kg(干重基础)。     

斑节对虾虾苗活力检测方法

该研究通过肉眼观察、镜检，进行干露、饥饿、盐度突降、福尔马林等抗性试验，并采用病毒检测等方法，以期建立评估斑节对虾（Penaeus monodon）虾苗活力和质量标准。结果表明，斑节对虾健康虾苗具有趋光性、集群性，体表光洁，肌肉透亮，肠胃食物充盈等特性。测试虾苗干露时间以15min为宜，健康虾苗干露后能立即恢复活力，而病弱虾苗多出现死亡、昏迷现象；虾苗的成活率随饥饿时间的延长而降低，随福尔马林浓度升高和时间延长而降低，随盐度突降幅度增加而降低。健康虾苗能忍受100～200μL·L^-1福尔马林溶液30min，成活率近100％；在盐度20～30下虾苗的成活情况较好，而其在淡水中仅能存活1h。对虾苗进行病毒检测，可以避免养殖中因虾苗携带病毒而可能导致的病毒性疾病的暴发。     

金鳟、虹鳟苗种长途运输实例

鳟鱼发眼卵和旨种运输是养鳟生产的重要环节。发眼卵多在冬季和早春运输，苗种多在晚春和夏季运输。苗种运输大多以鱼篓充氧进行短距离汽车运输，长途运输冷水性鱼苗种的实例很少。本文总结了金鳟和虹鳟苗种长途运输方法，以期与养鳟业界共同交流提高。一、包装材料和方法内包装材料是苗种运输专用塑料袋，规格54×104cm，外包装是泡沫塑料箱，规格63.5×45.5×30．5cm，纸箱规格64×46×32．5cm。塑料袋采取双层式，内装苗种和水共12.5kg，其中苗种0.5-1．3kg，100－2000尾。起运前苗种停食1－2天。运鱼用水水温调至6℃，鱼、水入袋后袋内…     

Characterization of protease inhibitors of seminal plasma of cyprinids

Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season).     

鱼类热忍耐温度研究进展

The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect: (1) The key parameters of temperature of thermal tolerance in fishes; (2) The influence factors of temperature of thermal tolerance in fishes; (3) The research methods of thermal effect of fishes; (4) The evaluation of effects of thermal pollution on fishes, especially, with the coastal power station will be‘built in China recent years, the effects of thermal discharge water on the marine fisheries resource wered iscussed.     

Histopathology of respiratory organs of certain air-breathing fishes of India

Air-breathing fishes have evolved bimodal respiratory mechanisms for exploitation of water (through gills and highly vascularized skin) as well as atmospheric air (through aerial respiratory organs, ABO). Mucous cells in these respiratory organs of variously stressed fishes exhibit periodic fluctuations in their density and staining properties. The main types of damage in the gills include congestion of blood capillaries (BLCs), periodic lifting and sloughing of respiratory epithelia of the secondary lamellae causing haemorrhage, extensive fusion of secondary lamellae and hyperplasia of the respiratory epithelia due to uncontrolled regeneration leading to asphyxiation, altered excretion, and death of the fish. Haemolysis has also been observed following lead exposure. The damage in the ABO of Heteropneustes fossilis includes sloughing of the epithelial cells, leading to haemorrhage causing decreased red blood corpuscles density and degeneration of the secondary gill lamellae with reduced respiratory area. Subsequent hyperplasia of the respiratory epithelia and fusion of gill lamellae increase the respiratory barrier distance. The BLCs often bulge out and protrude into the lumen, bringing blood nearer to air. The ladder-like pillar cell (PLC)-BLC components of the gill lamellae frequently collapse. Damage to the ABO of Channa striata is less severe. Often haemorrhaging due to bursting of extensively stretched BLCs causes aerial respiratory failure. Chloride cells of the ABOs also show hyperplasia. While the highly mucogenic epidermis of C. striata shows less damage, the epidermis of Clarias batrachus and H. fossilis shows severe wear and tear, sloughing, and haemorrhage. Side-by-side regeneration continues, causing altered histomorphology of the epidermis. The different gland cells also show periodic fluctuations in their density and staining. The dermis also shows severe damage with loosening of their connective tissue fibres. These fibres give stronger reactions for sulfated mucin that not only retain additional water molecules for continuance of skin breathing, but also bind the toxic ambient pollutants.     

牙鲆刺激隐核虫病的防治

2005年七、八月份,乐亭、滦南一带多家工厂化牙鲆养殖场发生刺激隐核虫病,此种病虫害发病急、传染快、死亡率高。发生过该病的养殖场牙鲆死亡率一般都在50％～80％之间,这种病害给牙鲆养殖业带来很大损失。