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<正> 随着养鳖业的发展,鳖的病害日趋严重,常给养鳖场造成重大损失。为了保证养鳖业的健康发展,我们对鳖的常见病进行了初步研究,并对其治疗方法进行了探索。现根据国内外的有关资料及近两年我们的研究和实践,对中华鳖的常见病及防治方法介绍如下。1 红脖子病 主要症状是:早期咽喉部充血红肿,厌食;中后期脖子变粗,充血,伸出壳外不能缩回,呼吸困难。解剖病鳖肠道内无食物,肝脏肿大。该病常发生于早春和 相似文献
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广东省养鳖业现状及其发展前景 总被引：1，自引：0，他引：1
本文就目前广东养鳖业发展现状,根据国内外市场鳖的供不应求,指出养鳖业具有巨大的发展潜力和美好前景。本文着重指出今后发展养鳖业,要着重解决好几个存在的问题,特别是种苗供应、缩短养殖周期和鳖病防治等问题,随着这些问题的逐步解决,广东养鳖业将会有更大的发展。 相似文献
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本文就目前广东养鳖业发展现状。根据国内外市场鳖的供不应求,指出养鳖业具有巨大的发展潜力和美好前景。本文指出今后发展养鳖业,要着重解决好几个存在的问题,特别是种苗供应。缩短养殖周期和鳖病防治等问题,随着这些问题的逐步解决,广东养鳖业将会有更大的发展。 相似文献
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<正> 近年来,我国养鳖业(尤其是温室养鳖等工厂化养殖)发展迅速,其疾病危害问题也日益突出。本文通过对有关资料的归纳研究,结合自己的实践,对常见鳖病及其防治方法作一介绍,供生产者参考。1 疱疹病 病鳖体质差,消瘦,反应迟钝,全身有明显的溃疡,溃疡面下陷,可达真皮甚至暴露出甲板。溃疡在分布上似有对称性, 相似文献
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1加温养鳖业的发展进程我国是世界上养鳖最早的国家，早在公元前470年范蠡所著《养鱼经》中就有养鳖(守神)的记述。近代，日本的养鳖业有了较快的进展，已有100多年的历史。20世纪70年代川崎义一等改常温饲养为工厂化加温饲养，打破鳖的冬眠期，使养鳖的周期从3～4年缩短到12～15个月。这项改革使日本的养鳖业进入一个新的发展时期。我国养鳖，始于20世纪20年代，中国大陆50年代才起步。80年代开始加温养鳖，证明鳖的冬眠是属于对自然环境抗寒的生理适应，非不可逆转的遗传属性。1986年湖南省水产研究所进行了“利用地热水养鳖技术的研究”… 相似文献
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本文介绍1995-1996年对福建省主要养鳖基地进行养殖鳖病害现场调研和样品分析的结果，现场调查的情况表明，我省主要养鳖地区病害情况较为严重。福建沿海地区养殖中华弊病害较闽北及闽西养鳖地区严重，1995年成活率分别为75%和60%，沿海养鳖地区最具威胁的病害是病毒性出血病的白底板病，而闽北养鳖地区养殖鳖的主要病害为真菌性白斑病。鳖病对我省养鳖业已造成巨大的经济损失，已是我省养鳖业的重要制约因素。建议有关部门加大鳖病研究力度，对引进鳖苗加强检疫。在养殖管理上进行调整以便适应新形势下养鳖业的发展。 相似文献
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日本鳖，又名中华鳖日本品系，与现本地所养的中华鳖、台湾鳖、杂交鳖比较，其特点为生长快、病害少、体形好、裙边宽厚、味道鲜美、肉质结实、胶质多等。2003年以来我们从种源着手，引进日本鳖进行繁育及养殖，探索其繁养特性，总结一套日本鳖的繁养技术，以逐步提高我县鳖的良种率，促进养鳖业发展。现将日本鳖的繁育技术和繁育试验结果等总结如下： 相似文献
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工厂化养鳖水质与鳖病防治 总被引：1，自引：0，他引：1
工厂化养鳖水质与鳖病防治随着工厂化养鳖业的不断发展，人们往往注重于饲料和养殖方法的提高，忽视了水质与生态环境的重要性，以至鳖病频发，给养鳖业带来本可避免的重大损失。本文谨就工厂化高密度养鳖的水质环境与鳖疾病的发生关系作点探讨．一、不良水质所引起的鳖病... 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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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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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
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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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Peter Howgate 《Journal Of Aquatic Food Product Technology》2013,22(5):516-532
It is well-established in fish technology that freshness should be measured primarily by sensory procedures, though considerable effort has been expended in looking for nonsensory alternatives. A variety of methods for sensory evaluation of freshness has been described and this historical review traces developments of these methods. Much of the source material derives from the research literature such as research journals and reports of research, and the use of sensory methods in commercial quality control has scarcely been documented. There is a brief discussion of possible future developments in sensory evaluation of freshness. 相似文献