共查询到19条相似文献，搜索用时 171 毫秒
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草鱼细菌性烂鳃病病原的研究 总被引：14，自引：0，他引：14
从患细菌性烂鳃病的草鱼病灶分离得滑动细菌M_(165),经多次水中感染(及反复分离、再感染),能使草鱼及多种池塘鱼类显症、死亡。M_(165)的生物学特性与鱼害粘球菌相似,但不能用Dworkin法快速诱生小孢子。该菌DNA碱基比为35.3％,与粘球菌有明显差异,采用柱状屈桡杆菌学名Fiexibacter columnaris (Davis)Leadbetter。 相似文献
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２００２年夏，鳗鱼烂鳃病发生频繁，个别养殖场损失严重，特别是土池养殖鳗鱼，用药治疗比较困难，一些养殖场为了节省治疗费用，不对症下药，采用一些国家明文禁止的兽药，结果损失更加巨大。现将有关鳗鱼烂鳃病发生的主要特点及综合防治方法作扼要介绍，供广大养殖业者参考。一、病因引起鳗鱼烂鳃病发生的主要因子有：由于寄生虫如纤毛虫、指环虫、拟指环虫感染鳃造成对鳃的损伤后，细菌继发性感染；原发性细菌感染，其病原主要有嗜水气单胞菌、柱状屈桡杆菌等；水中有机物含量高时，鳃霉寄生于鳃部血管引发细菌继发性感染；水质条件恶化… 相似文献
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沈阳市于洪区鱼场粘孢子虫、烂鳃并发症的发生、防治初探李长华，蒋吉生，边佩华，董杰（沈阳市水产科学研究所）沈阳市于洪区鱼种场是全国集约化养鲤高产典型。自１９８５年在沈阳市率先集约化养鲤以来，鱼病频繁发生。特别是１９９５年７月近１０Ｄ成鱼池暴发了粘孢子虫... 相似文献
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中华鳖『烂嘴、烂脖子、烂爪』致病菌的研究 总被引：2，自引：0，他引：2
笔者目前对我所“烂嘴、烂脖子、烂爪子”病鳖进行了致病菌的分离培养，菌种提纯、菌种鉴定、人工感染及药物敏感性等进行了研究，初步得知，该病的主要病原为嗜水气单胞菌。经药敏试验确定其对头孢哌酮、头孢噻肟、庆大霉素、妥布霉素、卡那霉素、氯霉素、丁胺卡那等敏感性较强。一、材料与方法１．试验用鳖：原发性病鳖及人工感染用鳖均来自本所，体重１５０～３００克。２．培养基：营养琼脂培养基、SS培养基、克氏双糖铁培养基。以上培养基经分装，高压灭菌２８小时培养过夜，无菌即可使用（SS培养基除外）。３．菌株：用无菌方法从患… 相似文献
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Chemotherapy of Cytophaga/Flexibacter-like bacteria (CFLB) infections in fish: studies validating clinical efficacies of selected antimicrobials 总被引：1，自引：0，他引：1
Abstract. In vitro and in vivo efficacies of commonly used chemotherapeutants were determined for Cytophaga johnsonae, Cytophaga psychrophila, Flexibacter colutnnaris and Flexibacter maritimus. Treatmeat of barramundi, Lutes calcarifer (Bloch), with oxolinic acid (OA) as a bath (50 ppm) or by mouth (10 mg kg−1 body weight) resulted in serum levels above the minimum inhibitory concentration (MIC) for F. columnaris and produced significant clinical efficacy ( P < 0.05). Amoxycillin (AM) was found to produce adequate serum levels against F. maritimus when used as a bath (200 ppm) or given orally (80 mg kg−1 body weight) to Atlantic salmon, Salmo salar L. and rainbow trout, Oncorhynchus mykiss (Walbaum), respectively. At these dose rates, this antibiotic was also clinically efficacious against F. maritimus ( P <0.05). Trimethoprim produced more than adequate serum levels for the control of F. maritimus when given as a bath (50 ppm) or orally (10 mg kg−1 body weight). Trimethoprim was significantly more protective than AM when tested in vivo ( P < 0.05). For C. johnsonae and C. psychrophila , the MIC values for OA and oxytetracycline were low, whereas that for TMP was high. Also, based on MIC values, C. psychrophila strains were more sensitive to AM and norfloxacin than C. johnsonae. 相似文献
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柱状嗜纤维菌血清型的研究 总被引：4，自引：0，他引：4
采用从各种患病淡水鱼类上分离到的柱状嗜纤维菌（Ｃｙｔｏｐｈａｇａｃｏｌｕｍｎａｒｉｓ）４０个菌株,通过交叉凝集和琼脂内扩散反应,研究了Ｃ．ｃｏｌｕｍｎａｒｉｓ的血清型。结果表明：根据不同菌株的热稳定性具有明显差别的现象,首次证明了从我国各地收集的Ｃｃｏｌｕｍｎａｒｉｓ菌存在３个不同的血清型。 相似文献
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呋喃唑酮降解菌株的分离鉴定及降解特性研究 总被引：1，自引：1，他引：0
从污染鱼塘底泥中筛选分离出一株能有效降解低浓度呋喃唑酮的细菌F5,经16S rDNA同源性序列分析,鉴定为铜绿假单胞菌(Pseudom onas aeruginosa)。30℃静置避光培养30 d后,该菌株对0.75、1.0和2.5 mg/L呋喃唑酮的降解率分别为58.8%、64.1%和38.2%。温度为20~25℃更有利于该菌株的降解作用,对1.0 mg/L呋喃唑酮降解率均能达85%。碳源和氮源浓度的提高均能促进该菌株的生长和对呋喃唑酮的降解。在0.5 mg/L低磷浓度下,该菌株生长受抑制但降解活性增加,对1.0 mg/L呋喃唑酮降解率达71.8%。 相似文献
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多种接种途径对翘嘴鳜细菌性烂鳃和败血症的免疫预防效果 总被引：6，自引：0，他引：6
多种接种途径对翘嘴鳜细菌性烂鳃和败血症的免疫预防效果陈昌福，周文豪（华中农业大学水产学院，武汉４３００７０）陈昌福等（１９９５）先后用从患细菌性烂鳃病的翘嘴鳜（ＳｉｎｉｐｅｒｃａｃｈｕａｔｓｉＢ．）上分离的柱状嗜纤维菌（Ｃｙｔｏｐｈａｇａｃｏｌｕｍｎ... 相似文献
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盐度对杂交东方鲀存活和摄食的影响 总被引：1，自引：0，他引：1
采用盐度骤变和渐变的方法,研究了盐度0、5‰、10‰、15‰、20‰、25‰、30‰、35‰、40‰、45‰、50‰、55‰、60‰共13个梯度对菊黄东方鲀(♀)×红鳍东方鲀(♂)杂交F1代存活和摄食的影响。研究表明,盐度从30‰骤变到15‰～50‰时,杂交F1存活率最高,显著高于盐度0、5‰、10‰、55‰和60‰梯度的存活率(P<0.05),其中盐度10‰的梯度中杂交F1代存活率约为33.3%,而盐度0、5‰、55‰和60‰梯度的存活率均低于1%;盐度5‰～50‰为杂交F1可摄食盐度,其中20‰～35‰是最佳摄食盐度。盐度渐变时,盐度5‰～50‰梯度中杂交F1代存活率最高,显著高于盐度0、55‰和60‰梯度的存活率(P<0.05),其中盐度0的梯度中杂交F1代存活率最低,约为12%;盐度0～60‰为杂交F1可摄食盐度,其中盐度20‰、25‰、30‰、35‰和40‰时,杂交F1摄食率无显著差异,在盐度30‰时摄食量和摄食率均达到最大。表明,菊黄东方鲀(♀)×红鳍东方鲀(♂)杂交F1代是广盐性鱼类,对盐度适应能力较强,而且适应盐度渐变的能力强于盐度骤变。 相似文献
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Abstract. During Autumn 1990, the possible presence of microbial pathogens was investigated in two discrete populations of anaemic (rainbow trout fry syndrome; RTFS) rainbow trout fry. Dense pure culture growth of three types of yellow pigmentcd bacteria were recovered from moribund and dead animals on low nutrient media. The cultures were identified as coryneforms. Cytophaga columnaris and Janthinobacterium sp. All taxa induced clinical disease (with similarities to RTFS) in rainbow trout fry. 相似文献
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Abstract. Eggs of female rainbow trout, Oncorhynchus mykiss (Walbaum), were fertilized and subsequently exposed to high eoncentrations of Pseudomonas fluorescens or Cytophaga sp. (106 cells/ml) for 45 min during water hardening. Eggs were placed in horizontal hatchery trays alongside sterile water-treated eggs and mortality rates were observed daily throughout incubation. Numbers and species of bacteria present on egg surfaces and within egg contents were monitored at the green stage (unfertilized), after hardening, and at 12h, 7 days, 14 days, 21 days and 28 days incubation. Surfaces of the incubating eggs of all groups, irrespective of treatment at water hardening, were eventually colonized by considerable numbers of Cytophaga sp., P. fluorescens and to a lesser extent Pseudomonas sp. and Aeromonas hydrophila. Few bacteria were recovered from inside eggs. Overall, no correlation was found between bacteria on the egg surface and egg death. However, a significantly higher 'rate' of egg death during early stages of incubation was found amongst eggs exposed to P. fluorescens at water hardening. Thus, high numbers of P. fluorescens on egg surfaces during initial stages of incubation might pose a potential threat to egg survival. Therefore, it is suggested that strenuous efforts are made at time of hardening to obtain the purest available source of water. 相似文献
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高温胁迫对刺参耐高温群体和普通群体主要免疫酶活力的影响 总被引：4，自引：3，他引：1
以定向选育的刺参(Apostichopus japonicus)耐高温品系子三代(F3组)和未经选育的普通刺参(C组)1龄幼参[(13.6±1.8)g/头]为研究对象,在室内模拟池塘夏季高温环境,比较了两个群体在25℃、27℃、29℃、31℃、32℃和33℃6个温度梯度下体壁抗氧化酶(SOD、CAT和T-AOC)、水解酶(ACP和AKP)和溶菌酶(LSZ)活力的差异。结果表明,在抗氧化酶活力方面,F3和C组刺参SOD活力均随温度的升高呈先升高后降低的趋势,且当温度为31℃和32℃时F3组SOD活力显著高于C组(P0.05);F3组CAT活力在实验温度范围内均高于C组,且当温度为27~31℃和33℃时差异显著(P0.05);F3组T-AOC活力在各温度下均显著高于C组(P0.05)。在水解酶活力方面,F3组的ACP活力在各温度下均高于C组,且除31℃外,其余温度下均差异显著(P0.05);F3组AKP活力在25℃、27℃和31℃下显著高于C组(P0.05),其余温度下差异不显著。F3和C组LSZ活力均随水温的上升呈先升高后降低的趋势,且在27~31℃范围内F3组LSZ活力显著高于C组(P0.05)。结果表明,经过定向选育的耐高温品系F3对高温的耐受能力获得了提高,实验结果为耐高温刺参良种选育提供了理论依据。 相似文献