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鲤指环虫病的暴发与诊治鲤鱼指环虫病的病原为坏鳃指环虫,主要寄生在鲤鱼的鳃上,大量寄生时引起鳃组织的损害,造成鱼体呼吸困难而死亡。1995年9月下旬,四川三台和盐亭县两个湖的渔场网箱鲤鱼同时暴发指环虫病,该病来势猛、发病急,几天之内就引起鲤鱼大批死亡,... 相似文献
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本文记述了寄生于乌原鲤鳃上的指环虫两新种。作者分别定名为:囊阴指环虫(新种)Dactylogyrus cystovagina sp.nov.,和剥隘指环虫(新种)Dactylogyrus boaiensis sp.nov.。 相似文献
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为验证依靠形态鉴定的指环虫种类的正确性,进行了分子生物学鉴定,并研究了系统发育。2009-2014年在额尔齐斯河采集的银鲫(Carassius auratus gibelio)鳃部的指环虫,依靠形态鉴定为坏鳃指环虫(Dactylogyrus vastator)和伸展指环虫(Dactylogyrus extensus)。18S rDNA序列与Gen Bank中18S rDNA序列同源性比较结果,坏鳃指环虫同源性为99.36%(457/460),碱基转换率为0.65%(3/460);伸展指环虫同源性为100%(472/472)。用MEGA4.1软件分析和计算3科8属19种单殖吸虫18S r DNA序列的遗传距离。3个科单殖吸虫种类的种间遗传距离0.006~0.238,指环虫科的遗传距离0.007~0.047,指环虫科与锚首虫科的遗传距离0.097~0.182,指环虫科与鳞盘虫科的遗传距离0.164~0.235。系统发育研究结果,坏鳃指环虫和中间指环虫首先聚为一支,然后与伸展指环虫聚为一支,最终指环虫科的所有虫种聚为一支。研究结果同时也为额尔齐斯河人工养殖银鲫的病害防治提供依据。 相似文献
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寄生在鱼类躯体及鳃上的单殖类吸虫(Monoge- nea)种类很多,至今已发现大约有200多种,其中以拟指环虫危害最为严重。在鳗鲡鳃上寄生的拟指环虫(Psuedodactylogyrus),常见的有3种:小拟指环虫(P.mincrorchis)、短钩拟指环虫(P.bini)以及鳗拟指环虫(P.angullae)。其中以短钩指环虫个体较大,体长可达1.63 mm,其余2种个体较小;它们对目前东南沿海地区普遍饲养的欧鳗构成很大的威胁。由镜检可见:拟指 相似文献
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鲤鱼指环虫病的暴发与诊治报道汪开毓(四川农业大学动物科技学院,雅安625014)鲤鱼指环虫病的病原为坏鳃指环虫,该虫主要寄生在鲤鱼的鳃上,大量寄生时会引起鳃组织的损害,造成鱼体呼吸困难而死亡。1995年9月下旬,四川三台和盐亭县两个湖渔场网箱内养殖的... 相似文献
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欧鳗拟指环虫病的几种有效防治方法 总被引:1,自引:0,他引:1
在欧鳗养殖过程中,拟指环虫病是发病率高、危害大的一种常见病,在生产上一般采用0 7g/m3甲苯咪唑杀灭拟指环虫来治疗该病。但由于拟指环虫易产生耐药性,有些养殖场甲苯咪唑用量增加到1 5g/m3,仍无法驱除拟指环虫,使原本有效的药物疗效不佳,超高浓度用药在高温作用下又易对欧鳗产生毒害作用,引发烂鳃和脱粘败血病。为此,福建省三明市牧渔良种繁育场通过近几年的生产实践,总结出几种有效的欧鳗拟指环虫病防治方法,现介绍如下,供欧鳗养殖人员参考。1 病因病原为单殖吸虫,属多钩亚纲指环虫科,由短钩拟指环虫或鳗拟指环虫感染引起,虫体… 相似文献
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水硬度对七彩神仙鱼幼鱼发育的影响 总被引:4,自引:0,他引:4
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。 相似文献
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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. 相似文献
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《水生生物资源》2003,16(5):461-465
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). 相似文献
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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。 相似文献
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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。 相似文献
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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… 相似文献
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牙鲆刺激隐核虫病的防治 总被引:1,自引:0,他引:1
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。 相似文献
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该研究选取具有多态性的6对微卫星引物对构建的2批合浦珠母贝(Pinctada fucata)完全双列杂交家系的遗传多样性进行了分析。6个微卫星标记在9个家系360个个体中共检测到32个等位基因,有效等位基因(Ne)为1.758 7~3.586 5,观测杂合度(Ho)为0.144 4~0.488 9,期望杂合度(He)为0.432 0~0.722 2,Shannon指数(I)为0.691 9~1.507 4。9个家系都有单态位点,平均Ho为0.129 2~0.466 7,平均He为0.155 0~0.439 6,平均I为0.248 5~0.712 2。有19个位点(占35.19%)极显著地偏离Hardy-Weinberg平衡。各家系之间的遗传距离为0.109 0~1.137 2,遗传相似性系数为0.320 7~0.896 8。家系L4B46与L4B48的遗传距离最大,与D3D313的遗传距离最小。UPGMA法聚类分析显示,9个家系分为3支,L4B48单独成一支,B4D426、B4D427与D4B445聚成一支,其余家系聚成一支。该研究结果为合浦珠母贝家系选择育种的亲本选择与交配设计提供了科学依据。 相似文献