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Development of a two‐step,non‐probed multiplex real‐time PCR for surveilling Vibrio anguillarum in seawater 下载免费PDF全文
Vibrio anguillarum is an aggressive and halophilic bacterial pathogen most commonly originating from seawater. Vibrio anguillarum presence in fisheries and aquaculture facilities causes significant morbidity and mortality among aquaculture species primarily from haemorrhaging of the body and skin of the infected fish that eventually leads to death, collectively recognized as the disease vibriosis. This study served to develop a non‐probe, multiplex real‐time PCR assay to rapidly detect V. anguillarum presence in seawater. Specific primers targeting genes vah1, empA and rpoN of V. anguillarum were selected for multiplex reaction among 11 different primer sets and the extension step was eliminated. Primer concentration, denaturation time as well as annealing time and temperature of DNA amplification were optimized, thus reducing reaction duration. The two‐step, non‐probed multiplex real‐time PCR set forth by this study detects as little as 3 CFU mL?1 of V. anguillarum presence in sea water, without enrichment cultivation, in 70 min with molecular precision and includes melting curve confirmation. 相似文献
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Enhanced immune responses and effectiveness of refined outer membrane protein vaccines against Vibrio harveyi in orange‐spotted grouper (Epinephelus coioides) 下载免费PDF全文
Hai Trong Nguyen Thuy Thi Thu Nguyen Yan‐Chun Chen Hung Vu‐Khac Pei‐Chi Wang Shih‐Chu Chen 《Journal of fish diseases》2018,41(9):1349-1358
Vibriosis is a severe infection occurring in many commercially important marine fish species. In this study, vaccines containing Vibrio harveyi recombinant outer membrane protein K (rOmpK), outer membrane protein U (rOmpU) and rOmpK‐OmpU fusion protein in addition to the metabolizable MontanideTM ISA 763 A VG adjuvant were developed and evaluated in the orange‐spotted grouper. The results indicate that recombinant V. harveyi protein‐based vaccines resulted in a remarkably higher expression of IL‐1β and IL‐8 at 24 hr, and greater antibody production, as early as 2 weeks postimmunization. Notably, enhanced immune responses and significant protective efficacy against V. harveyi infections were observed in the fusion protein vaccine‐injected fishes with relative per cent survival value of 81.8%. Additionally, the rOmpK‐OmpU antisera presented a high bactericidal effect on not only V. harveyi, but also Vibrio parahaermolyticus and Vibrio alginolyticus. Our results demonstrated that the fusion protein rOmpK‐OmpU was an effective vaccine candidate that exhibited potentially great versatility for controlling vibrio infections. 相似文献
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Analysis of the relationship between luminescence and toxicity of <Emphasis Type="Italic">Vibrio carchariae</Emphasis> pathogenic to shrimp 总被引:1,自引:0,他引:1
Tatsuya?Nakayama Nakao?Nomura Masatoshi?MatsumuraEmail author 《Fisheries Science》2005,71(6):1236-1242
ABSTRACT: Aquaculture deterioration is caused by Vibrio harveyi , which is one of the main shrimp pathogens. Vibrio carchariae having the same phenotypic characteristics as V. harveyi was isolated from a shrimp farm and used in this study to investigate the relationship between luminescence and toxicity. Luminescence was verified by monitoring the expression of the LuxR gene. It was found that the relationship between the expression of LuxR and toxicity was the most significant factor related to luminescence. Results showed that LuxR expression was highest after 20 h of culture, which is comparable to the highest scintillation counter luminescence value (20 h). However, toxin levels in the culture broth were highest between 24 h-36 h of culture. Significant decrease in the toxicity level was observed after 36 h. It was also found that there was a decrease in toxicity level after 12 h of incubation at room temperature of the V. carchariae culture supernatant. The effect of the addition of cell-free culture supernatant on the luminescence of V. carchariae was also determined. Results showed that the addition of cell-free supernatant from 24 h-old culture was most effective in inducing and maintaining luminescence. 相似文献
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文蛤病原菌(溶藻弧菌)的分离与性状及病文蛤组织的电镜观察 总被引:37,自引:1,他引:37
近年来,江苏南部沿海在8~10月份常发生文蛤大批死亡,从病文蛤体内分离到病原菌,经人工感染试验得到证实。病原菌为革兰氏阴性短杆菌,以极生单鞭毛运动,在TCBS琼脂平板上形成黄色大菌落,在固体培养基上能游动。发酵葡萄糖产酸不产气,精氨酸—碱反应阴性,赖氨酸、鸟氨酸脱羧阳性。在无盐蛋白胨水中不能生长,在10%NaCl 蛋白胨水中生长良好。在43℃下能正常繁殖。对弧菌抑制剂0/129(150μg)和新生霉素(5μg)敏感,被鉴定为溶藻弧菌(Vibrio alginolyticus Sakazaki)。病文蛤超薄切片的电镜观察表明,肠上皮及肝组织被细菌侵袭。病原菌在肠上皮细胞质中增生,形成上百个细菌的集群。上皮细胞核变形,被挤向一侧,线粒体内嵴模糊,部分上皮细胞微绒毛的结构被严重破坏,细菌周围的组织被腐蚀成空斑。 相似文献
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Infections caused by antibiotic resistant luminescent vibrios can cause considerable losses in aquaculture. In this study, different short-chain fatty acids were investigated as possible alternative biocontrol agents. The addition of 100 mM formic, acetic, propionic, butyric or valeric acid to the growth medium of a pathogenic Vibrio campbellii strain completely inhibited its growth at pH 6. At 10 mM, the growth of the pathogen was delayed, whereas at 1 mM, no effect could be observed. The growth-inhibitory effect was clearly pH-dependent and decreased with increasing pH. An in vivo challenge test with gnotobiotic Artemia franciscana nauplii revealed that all five short-chain fatty acids protected the shrimp from the pathogenic V. campbellii strain. The addition of 20 mM of the short-chain fatty acids to the culture water resulted in a significantly increased survival of infected nauplii, with no difference between the different fatty acids. In conclusion, our data indicate that short-chain fatty acids might be useful as alternative biocontrol agents to treat luminescent vibriosis. 相似文献
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A L Smith M M A Whitten L Hirschle E C Pope E C Wootton C L Vogan A F Rowley 《Journal of fish diseases》2014,37(8):729-737
Juvenile edible crabs, Cancer pagurus L., were surveyed from Mumbles Head and Oxwich Bay in South Wales, UK, and the number of heterotrophic bacteria and vibrios in the hemolymph was determined. The percentage of crabs with hemolymph containing bacteria was variable over the survey with higher numbers of animals affected in summer than in winter. Post‐moult crabs contained significantly higher numbers of heterotrophic bacteria in the hemolymph than pre‐ and intermoult animals. Crabs with cuticular damage to the gills also had significantly higher numbers of bacteria in the hemolymph. Crabs were found to have a high prevalence of infection by the dinoflagellate, Hematodinium. Such animals had significantly fewer bacteria in the blood in comparison with Hematodinium‐free animals. Of the 463 crabs surveyed, only 3 individuals had hemolymph containing 2000 + CFU mL?1. Based on 16S rRNA gene sequences, two of these crabs contained a Vibrio pectenicida‐like isolate, while the other had a mixed assemblage of vibrios. Although 59% of the crabs surveyed had culturable bacteria in the hemolymph, the majority only had small numbers (<2000 CFU mL?1), suggesting that such infections may be of limited importance to the sustainability of the crab fishery in this region. 相似文献
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Resistance to vibriosis,production performance and tolerance to stress of the selected giant freshwater prawn (Macrobrachium rosenbergii) 下载免费PDF全文
Ikhsan Khasani Angela Mariana Lusiastuti Muhammad Zairin Alimuddin Alimuddin 《Aquaculture Research》2018,49(1):273-281
The purpose of this study was to evaluate the resistance to vibriosis, growth, survival and tolerance to stress of the selected prawn, second generation, compared to a non‐selected control. The first generation of selected giant freshwater prawn, which has 10.4% higher of resistance, was used to attain disease resistant freshwater prawn (Macrobrachium rosenbergii) generation through challenge test‐based selection. Resistance test was conducted by infecting the prawn (mean body weight of 10.29 ± 1.40 g) with pathogenic Vibrio harveyi (5 × 105 cfu prawn?1). The growth and survival of the prawn were evaluated by rearing the two populations of prawn in both nursery and grow‐out phases. Stress tolerance test was done by evaluating the viability of postlarvae exposed to environmental stressors, i.e. temperature, salinity, NH3 and formaldehide. Post‐challenge survival of the selected prawn (55.0 ± 5.0%) was about 46% higher than that of the control (37.5 ± 7.5%). The survival of the selected prawn in nursery culture (77.16 ± 0.841%) was significantly higher (p < .05) than that of the control (51.31 ± 2.938%), while the survival in grow‐out culture was similar (p > .05). The growth of selected prawn (4.99 ± 0.03% day?1) was significantly higher than that of the control (4.81 ± 0.05% day?1). There was no difference between treatments on the tolerance level against the tested environmental stressor. Overall data suggested that the selected prawn showed better performance in growth and resistance against vibriosis. 相似文献