排序方式： 共有18条查询结果，搜索用时 15 毫秒
1.
温和气单胞菌TL97528株丝氨酸蛋白酶基因片段克隆与序列分析 总被引：1，自引：0，他引：1
中华鳖(Trionyx sinensis)细菌性疾病主要由气单胞菌感染引起的,通过脱脂奶平板检测及酶活性试验得出温和气单胞菌TL97528株分泌的胞外蛋白酶为丝氨酸蛋白酶,而丝氨酸蛋白酶是气单胞菌的主要毒力因子。根据已发表的嗜水气单胞菌的丝氨酸蛋白酶基因序列保守区域设计引物,PCR扩增出一长度为809 bp大小的特异片段,该序列在Genbank上的登录号为FJ357446。对该序列进行分析发现,已发表的温和气单胞菌(Aeromonas sobria)丝氨酸蛋白酶基因(GenBank登录号为AF253471)同源性为98%、与其他几株已发表的嗜水气单胞菌(Aeromonas hydrophila)丝氨酸蛋白酶基因(GenBank登录号分别为AF126213、AY841795、DQ127822、CP000462、CP000644、AF159142)同源性分别为98%、82%、82%、82%、81%、81%,与杀鲑气单胞菌(Aeromonas salmonicida)丝氨酸蛋白酶基因(GenBank登录号为X67043)同源性为80%。用DNAstar软件分析,与鳖源温和气单胞菌TK961010株的同源性为98%,... 相似文献
2.
团头鲂对3种致病菌外膜蛋白(OMP)的免疫应答 总被引：1，自引：0，他引：1
利用从柱状黄杆菌(Flavobacterium columnare)、嗜水气单胞菌(Aeromonas hydrophila)和温和气单胞菌(Aeromonas sobria)中提取的外膜蛋白(outer membrane protein,OMP)作为免疫原,注射接种团头鲂(Megalobrama amblycephala)后,通过测定受免鱼的交叉凝集抗体效价、肾脏和血液中吞噬细胞的吞噬活性和采用A.hydrophila活菌攻毒方法,比较了3种致病菌OMP对团头鲂的免疫原性。试验结果表明,从3种致病菌中提取的OMP对团头鲂均具有较强的免疫原性,受免鱼的血清中存在对3种致病菌的交叉凝集抗体,与对照鱼相比,肾脏和血液中吞噬细胞对吞噬原的吞噬活性和对A.hy-drophila活菌攻毒的相对免疫保护率(relative percent survival,RPS)明显上升。说明在3种致病菌的OMP上不同程度地存在共同保护性抗原。 相似文献
3.
嗜水气单胞菌脂多糖对乌鳢抗氧化性能及其他生理功能的影响 总被引：1，自引：0，他引：1
摘要：以乌鳢为试料,研究灭活嗜水气单胞菌脂多糖（LPS）对其抗氧化性能、免疫功能及消化功能的影响,试验结果表明嗜水气单胞菌LPS能提高乌鳢的抗氧化性能、免疫功能及消化功能,但不同浓度脂多糖的生理作用不同,0.8 mg/ mL组可提高乌鳢的抗氧化性能：在第10天时血液CAT酶活力达0.17U、SOD酶活力为16.56U/mg,均比对照（CK）组的高;0.6 mg/ mL嗜水气单胞菌脂多糖能提高乌鳢血液溶菌酶、胃肠道淀粉酶、蛋白酶的活力：0.6mg/ mL组LPS处理的乌鳢血液溶菌酶活力到第20天时为最高,达到0.0399U,在第10天时,淀粉酶活力为17.21U,蛋白酶活力为0.36U,均高于对照组。 相似文献
4.
5.
鳖疖疮病病原的分离与鉴定 总被引：1，自引：0，他引：1
1988年冬到1989年春,我院从某特种水产科研所引进的稚鳘发生了一种新的传染病,病鳖体表形成疖状病灶,暂名为鳖疖疮病。从病鳖的病灶和脏器内分离到两株细菌,经腹腔注射和伤口涂抹能使健康鳖表现出与自然发病相同的病症。两菌株的特性基本一致,被鉴定为点状产气单胞菌点状亚种。 相似文献
6.
The in vitro efficacy of oxytetracycline against re‐isolated pathogenic Aeromonas hydrophila carrying the cytolytic enterotoxin gene through hybrid catfish,Clarias macrocephalus (Günther, 1864) × Clarias gariepinus (Burchell, 1822) in Thailand 
下载免费PDF全文
下载免费PDF全文 Pongsaton Juntarut Sanae Kaewnopparat Damrongsak Faroongsarng Sommai Chiayvareesajja 《Aquaculture Research》2018,49(5):1848-1857
Aeromonas hydrophila is a pathogen infecting farmed hybrid catfish, Clarias macrocephalus (Günther, 1864) × Clarias gariepinus (Burchell, 1822) which incurs substantial economic losses in Thailand. The study aimed at a genetic tracking of A. hydrophila infection and the in vitro assessment of the efficacy of antibiotics against its virulent strains. Five clinical strains from catfishes and Nile tilapia were employed. They were 3‐passage re‐isolated through healthy hybrid catfish and the cytolytic enterotoxin gene (AHCYTOEN) of individuals was traced. Each of the re‐isolates at a dose of ~6.67 × 105 CFU/g was intraperitoneally injected into ~15 g‐healthy hybrid catfish and their pathogenicity were observed for 7 days. It was found that AHCYTOEN was carried over whereas typical signs of motile aeromonas septicaemia were found in the specimens. The bacterial strains of Nile tilapia origin did not induce mortality but those of catfish origins (80%–100% rate of mortality). The strains were susceptible to the tetracycline antibiotics, and oxytetracycline produced MIC50 and MBC as low as 0.007–0.031 μg/ml and 1–8 μg/ml respectively. As oxytetracycline specifically inhibited pathogenic A. hydrophila in vitro, it is recommended that an appropriate dosage regimen of the drug should be established. 相似文献
7.
Enhancement of non‐specific immune responses in common carp,Cyprinus carpio,by dietary carotenoids obtained from shrimp exoskeleton 下载免费PDF全文
下载免费PDF全文 The immunostimulatory role of carotenoid extract from shrimp processing discards was evaluated by feeding common carp fingerlings with a diet containing carotenoid extract for 21 weeks at 100 and 200 mg kg?1 astaxanthin levels. Haemoglobin content was significantly (P < 0.05) higher in the blood of fish fed with carotenoid diet (>8.1 g dL?1) compared with that from fish fed with carotenoid deficient diet (6.86 g dL?1) and also leukocyte counts were higher (P < 0.05). No differences (P > 0.05) were observed in total serum protein, globulin level and albumin‐globulin ratio, but albumin content was higher (P < 0.05). Respiratory burst activity was significantly (P < 0.05) higher, the serum lysozyme activity almost doubled and the serum bactericidal activity was significantly increased when the fish were fed with diet containing 200 mg kg?1 of astaxanthin but no significant differences were observed in serum trypsin inhibitory activity. There was a significant (P < 0.05) increase in leukocyte myeloperoxidase activity due to dietary carotenoids. Challenging fish with Aeromonas hydrophila after the feeding period resulted in 50% mortality in the control group while in the group fed with diet containing 100 mg kg?1 astaxanthin, the mortality rate was 15%. No mortality and even symptoms of infection was not observed in the group fed with diet containing 200 mg kg?1 of astaxanthin. The study indicated that carotenoid extract from shrimp processing discards can effectively be used as immunostimulants in aquaculture of carps and dietary carotenoids were found to enhance various immune defence mechanisms and also provide protection against the infection of pathogen A. hydrophila. 相似文献
8.
为了建立一种快速、准确能早期检测草鱼肠炎病原菌的方法,以患病草鱼为材料,制备点状产气单胞菌单克隆抗体(McAb),并鉴定其特异性和抗原表位;采用过碘酸钠方法,以辣根过氧化物酶标记单抗,用试管凝集试验测定其活性;建立点状产气单胞菌McAb的双抗原夹心ELISA检测方法,确定包被单抗和酶标单抗的浓度,并测定其灵敏度和特异性。结果:1)获得了2株特异性强和抗原表位不同的单抗,其ELISA效价为1∶16 000。2)辣根过氧化物酶标记的抗体活性为1∶640。3)建立了包被抗体稀释度为1∶800、酶标抗体稀释度为1∶1 600的双抗原夹心ELISA检测方法,该方法与点状产气单胞菌呈强阳性反应,与近似菌无交叉反应,灵敏性为7×103cfu/mL。结论:制备的点状产气单胞菌McAb的效价高、特异性强;建立的双抗原夹心ELISA方法操作简单、灵敏度高、特异性强,可应用于草鱼肠炎病原体的早期快速检测。 相似文献
9.
为初探虹鳟鱼源杀鲑气单胞菌对杂交鲟是否具有感染性及人工感染后的主要临床症状及病理变化。本研究使用虹鳟鱼源杀鲑气单胞菌对杂交鲟进行人工感染,通过对半数致死量的测定、临床症状观察、发病杂交鲟解剖学变化观察及组织病理切片观察(HE染色)来确定杀鲑气单胞菌对杂交鲟是否具有致病性及致死性。结果显示:虹鳟鱼源杀鲑气单胞菌对杂交鲟具有感染性且存在致死性,臀鳍注射半数致死量为7.9×106CFU/mL;杂交鲟体表黏液分泌量增多,腹壁有大量出血点及溃疡灶,体内多器官伴随有出血点,严重者有溃疡灶形成,病理切片观察发现,感染后杂交鲟的鳃、肌肉、脂肪、肠道和心脏等组织均有明显的病理变化,其中病理变化较明显的为鳃丝的扭曲脱落,肠绒毛的脱落及肝脏细胞的空泡化变性。结果表明,杀鲑气单胞菌能引起杂交鲟发病,且具有致死性,其主要临床症状与疖疮病相同。 相似文献
10.
Dot-ELISA快速检测鱼类运动性气单胞菌的研究 总被引：2，自引：2，他引：2
制备了引起常见鱼病的６株运动性气单胞菌的兔抗血清，建立了检测运动性气单胞菌的Ｄｏｔ－ＥＬＩＳＡ法。该法能检出含１０７菌细胞／ｍＬ的菌悬液及１０个菌细胞／ｍＬ增菌２０ｈ的培养物，与运动性气单胞菌群内的菌株，均呈现明显的阳性反应，不与鲁克耶尔森氏菌、荧光假单胞菌、鳗弧菌等１０株对照菌发生影响检测结果的交叉反应。应用Ｄｏｔ－ＥＬＩＳＡ与常规分离法分别对人工感染的４０份样本进行检测，其阳性数分别为３３和３４，两法符合率为９７％。经Ｘ２检验表明，两法检测结果间有显著意义的一致性（Ｐ＜０．０５），但前者可在２４ｈ内报告结果。应用Ｄｏｔ－ＥＬＩＳＡ又对８株鱼源菌检定，结果与细菌学检查相符。Ｄｏｔ－ＥＬＩＳＡ法具有快速、敏感、特异、实用的优点，可用于引起常见鱼病的运动性气单胞菌群的检测。 相似文献