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1.
Vendrell D Balcázar JL Ruiz-Zarzuela I de Blas I Gironés O Múzquiz JL 《Comparative immunology, microbiology and infectious diseases》2006,29(4):177-198
Lactococcus garvieae is the etiological agent of Lactococcosis, an emergent disease which affects many fish species and causes important economic losses both in marine and freshwater aquaculture when water temperature increases over 16 degrees C in summer months. Normally, it causes a hyperacute and haemorrhagic septicemia. This paper presents a state of the art review of fish Lactococcosis including aspects such as pathogen characterization, pathogenesis, epidemiology, diagnosis and control measures of the disease in farmed fish. 相似文献
2.
El Aamri F Real F Acosta F Acosta B Valdivia J Ramos-Vivas J Padilla D 《Journal of aquatic animal health》2012,24(3):165-170
Streptococcus iniae is a major fish pathogen producing invasive infections that result in economic losses in aquaculture. Gentamicin protection assays were used to investigate the ability of different S. iniae strains to invade and adhere to fibroblastic-like fish cell line SAF-1. All strains tested were detected intracellularly using both techniques, with variable internalization degrees between strains. The experiments carried out at 4°C demonstrated that active cell metabolism is necessary for bacterial internalization. Intracellular bacteria were detected for up to 3 d with a round morphology and were stained with 4',6-diamidino-2-phenylindole (DAPI), indicating that some bacterial cells may remain viable inside SAF-1 cells. Our in vitro findings indicate that S. iniae is capable of adhering, entering, and surviving within fibroblastic cells, which may be important for the persistence and establishment of a carrier state. 相似文献
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This paper describes the main features of fish aquaculture in Europe and Italy focusing attention on single sectors of the farmed species and their trend for the future. Over recent years, European and Italian aquaculture have shown a markedly different trend from that of world aquatic production. Asia, particularly China, has recorded a constant and rapid growth and Latin America a moderate development. Nowadays, European farmers are concerned with adapting their product to market demand and diversifying the fish species reared. After a discussion about the main European production statistics regarding finfish aquaculture production, we consider the most important aspects in the promotion of production and consequent consumption of farmed fish. 相似文献
4.
This paper describes the main features of fish aquaculture in Europe and Italy focusing attention on single sectors of the
farmed species and their trend for the future. Over recent years, European and Italian aquaculture have shown a markedly different
trend from that of world aquatic production. Asia, particularly China, has recorded a constant and rapid growth and Latin
America a moderate development. Nowadays, European farmers are concerned with adapting their product to market demand and
diversifying the fish species reared. After a discussion about the main European production statistics regarding finfish aquaculture
production, we consider the most important aspects in the promotion of production and consequent consumption of farmed fish. 相似文献
5.
Buchanan JT Colvin KM Vicknair MR Patel SK Timmer AM Nizet V 《Veterinary microbiology》2008,131(1-2):145-153
Streptococcus iniae is a major fish pathogen producing invasive infections that result in economic losses in aquaculture. Development of in vitro models of S. iniae virulence may provide insight to the pathogenesis of infection in vivo. Three S. iniae strains (K288, 94-426, and 29178) were tested for virulence in a hybrid-striped bass (HSB) model using intraperitoneal injection. S. iniae strains K288 and 94-426 caused high levels of mortality in HSB (lethal dose 2x10(5)CFU) while strain 29178 was avirulent even upon IP challenge with 1000-fold higher inocula. In vitro assays were developed to test for the presence of characteristics previously associated with virulence in other species of pathogenic Streptococcus in animals and humans. In vitro differences relevant to virulence were not detected for beta-hemolysin activity, sensitivity to antimicrobial peptides, or adherence and invasion of epithelial cell layers. However, in whole-blood killing assays, the pathogenic strains were resistant to blood clearance, while 29178 was cleared (P<0.001) and more sensitive to complement (P<0.001). The avirulent strain 29178 was most efficiently phagocytosed and was most susceptible to intracellular killing (P<0.01) by the carp leukocyte cell line (CLC). When exposed to reactive oxygen species, strain 29178 was most susceptible. When the oxidative burst of CLC cells was inhibited, intracellular survival of 29178 was rescued fivefold, while no significant enhancement in survival of K288 or 94-426 was detected. Our results indicate that resistance to phagocytosis, oxidative killing, and associated phagocytic clearance is a significant factor in S. iniae virulence. 相似文献
6.
Transmission of the microsporidian gill parasite, Loma salmonae 总被引：1，自引：0，他引：1
Becker JA Speare DJ 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2007,8(1):59-68
Since it was first reported in 1987 at a hatchery in British Columbia, Loma salmonae has become increasingly important as an emerging parasite affecting the Canadian salmonid aquaculture industry. L. salmonae causes Microsporidial Gill Disease of Salmon (MGDS) in farmed Pacific salmonids, Oncorhynchus spp., resulting in respiratory distress, secondary infections and high mortality rates. In the last decade, laboratory studies have identified key transmission factors for this disease and described the pathogenesis of MGDS. L. salmonae enters the host via the gut, where it injects sporoplasm into a host cell, which then migrates to the heart for a two-week merogony-like phase, followed by a macrophage-mediated transport of the parasite to the gill, with a final development stage of a spore-laden xenoma within the endothelial and pillar cells. Xenoma rupture triggers a cascade of inflammatory events leading to severe, persistent, and extensive proliferative branchitis. The development of robust and reliable experimental challenge models using several exposure methods in marine and freshwater environments with several fish hosts, is a primary reason for the success of scientific research surrounding L. salmonae. To date, demonstrated factors affecting MGDS transmission include host species, strain and size, the length of contact time between na?ve and infected fish, water temperature and flow rates. 相似文献
7.
Numerous diseases have emerged as serious economic or ecological problems in aquaculture species. The combination of factors behind the emergence of each disease is unique, but various common factors are apparent. We combine risk-analysis methods and virulence theory with historical examples (mainly from salmonid production) to identify key disease-emergence risk factors. Diseases have emerged through pathogen exchange with wild populations, evolution from non-pathogenic micro-organisms and anthropogenic transfer of stocks. Aquacultural practices frequently result in high population densities and other stresses (such as intercurrent disease) which increase the risk of infection establishment and spread. As aquaculture expands and new species are farmed, diseases will continue to emerge and affect both wild and farmed fish adversely. The rate and extent of emergence can be reduced by the application of biosecurity programmes designed to mitigate the risk factors for disease emergence. 相似文献
8.
Over 1 billion ornamental fish comprising more than 4000 freshwater and 1400 marine species are traded internationally each year, with 8-10 million imported into Australia alone. Compared to other commodities, the pathogens and disease translocation risks associated with this pattern of trade have been poorly documented. The aim of this study was to conduct an appraisal of the effectiveness of risk analysis and quarantine controls as they are applied according to the Sanitary and Phytosanitary (SPS) agreement in Australia. Ornamental fish originate from about 100 countries and hazards are mostly unknown; since 2000 there have been 16-fold fewer scientific publications on ornamental fish disease compared to farmed fish disease, and 470 fewer compared to disease in terrestrial species (cattle). The import quarantine policies of a range of countries were reviewed and classified as stringent or non-stringent based on the levels of pre-border and border controls. Australia has a stringent policy which includes pre-border health certification and a mandatory quarantine period at border of 1-3 weeks in registered quarantine premises supervised by government quarantine staff. Despite these measures there have been many disease incursions as well as establishment of significant exotic viral, bacterial, fungal, protozoal and metazoan pathogens from ornamental fish in farmed native Australian fish and free-living introduced species. Recent examples include Megalocytivirus and Aeromonas salmonicida atypical strain. In 2006, there were 22 species of alien ornamental fish with established breeding populations in waterways in Australia and freshwater plants and molluscs have also been introduced, proving a direct transmission pathway for establishment of pathogens in native fish species. Australia's stringent quarantine policies for imported ornamental fish are based on import risk analysis under the SPS agreement but have not provided an acceptable level of protection (ALOP) consistent with government objectives to prevent introduction of pests and diseases, promote development of future aquaculture industries or maintain biodiversity. It is concluded that the risk analysis process described by the Office International des Epizooties under the SPS agreement cannot be used in a meaningful way for current patterns of ornamental fish trade. Transboundary disease incursions will continue and exotic pathogens will become established in new regions as a result of the ornamental fish trade, and this will be an international phenomenon. Ornamental fish represent a special case in live animal trade where OIE guidelines for risk analysis need to be revised. Alternatively, for countries such as Australia with implied very high ALOP, the number of species traded and the number of sources permitted need to be dramatically reduced to facilitate hazard identification, risk assessment and import quarantine controls. 相似文献
9.
Andrea Paloma Zepeda-Velázquez Vicente Vega-Sánchez Celene Salgado-Miranda Edgardo Soriano-Vargas 《Canadian journal of veterinary research》2015,79(3):250-254
This study describes the macroscopic and microscopic lesions in farmed rainbow trout (Oncorhynchus mykiss) naturally infected with genetically identified Aeromonas salmonicida, A. hydrophila, and A. veronii species. The genus Aeromonas includes bacteria that naturally inhabit both waterways and organisms. At least 27 Aeromonas species have been identified to date, some of which can cause significant economic losses in aquaculture. As up to 68.8% of Aeromonas isolates may be misidentified in routine biochemical and phenotypic tests, however, reported cases of Aeromonas infection in fish may be wrongly identified. Our findings confirmed that the 3 Aeromonas species studied are associated with septicemia and dermal lesions in rainbow trout. 相似文献
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Streptococcus iniae is one of the most economically important Gram-positive pathogens in cultured fish species worldwide. The USDA-ARS Aquatic Animal Health Research Unit developed a modified (contains concentrated culture supernatant) S. iniae bacterin that has been demonstrated to be efficacious, and protection is mediated by specific anti-S. iniae antibodies. Although effective, the specific vaccine components important for efficacy are not known. In the present study, an immunoproteomic approach was utilized to identify whole-cell lysate proteins of S. iniae that stimulated specific antibody production in Nile tilapia (Oreochromis niloticus) following vaccination. Groups of tilapia were vaccinated by intraperitoneal injection with the modified S. iniae bacterin or were mock-vaccinated, and at 30 d post-vaccination sera samples were obtained from individual fish. Vaccination of tilapia with the S. iniae vaccine stimulated significantly elevated specific antibody responses against proteins of the bacterium and passive immunization of tilapia with this serum demonstrated the antibodies were highly protective. Whole-cell lysate proteins of S. iniae were separated by 2D-PAGE and were probed with a pooled serum sample from vaccinated tilapia. A total of eleven unique immunogenic proteins were positively identified by mass spectrometry. Based on research conducted on homologous proteins in other Streptococcus spp., antibodies specific for three of the identified proteins, enolase, glyceraldehyde-3-phosphate dehydrogenase, and fructose-bisphosphate aldolase, are likely involved in protection from streptococcosis caused by S. iniae. 相似文献
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Ghittino C Latini M Agnetti F Panzieri C Lauro L Ciappelloni R Petracca G 《Veterinary research communications》2003,27(Z1):471-479
Infectious diseases represent a limiting factor for the further development of Italian aquaculture. The recent introduction and spreading of new pathogens, along with the global climatic change, has contributed to a considerable decrease in trout production. Emerging pathologies in rainbow trout culture include viral diseases, e.g. infectious haematopoietic necrosis (IHN), bacterial diseases, such as lactococcosis and visceral flavobacteriosis, and parasitical diseases, e.g. proliferative kidney disease (PKD). Higher mortality rates in trout fry and fingerlings are generally induced by visceral flavobacteriosis and IHN, while the main losses in large trout during the warm season are due to lactococcosis and PKD. Mariculture has at present a better sanitary status compared to trout culture, but a rapid dissemination of pathogens, including zoonosis agents, is envisaged also for seabass and seabream. Emerging pathologies in sea bass include VNN, pseudotuberculosis, streptococcosis and tuberculosis. Seabream is much more resistant and is mainly affected by novel Vibrio infections and enteromyxidiosis. A good sanitary management of fish farms is essential for avoiding or limiting losses caused by emerging pathologies. Transmission of zoonosis agents to man, through the consumption of cultured fish, is very remote in Italy. On the contrary, transmission of Streptococcus iniae, Vibrio vulnificus and Mycobacterium marinum by means of improper manipulation of infected fish, could represent a potential hazard for fish farmers and fish processors, as well as for people preparing fish meals. 相似文献
14.
The crustacean ectoparasite, Argulus poses one of the major threats to carp culture due to absence of any suitable control measure. The study was undertaken to determine the expression of immune-related genes in three major immunocompetent organs viz., kidney, skin and liver of rohu (Labeo rohita) during experimental freshwater lice Argulus siamensis infection. Results showed that the expression of TLR 22-like, lysozyme G and β2-microglobulin genes in kidney was significantly (P ≤ 0.05) down-regulated in lice-infected fish. On the other hand, no significant difference (P>0.05) in CXCa, lysozyme C, TNFα and complement component 3 (C3) expression was found between uninfected control and different degrees of lice infected fish. In the skin, the expression of TLR 22-like and TNFα genes were significantly up-regulated whereas that of C3 was significantly (P ≤ 0.05) down-regulated in lice-infected fish with respect to control fish. The expression of CXCa, lysozyme C and transferrin was not detected in the skin samples of fish. In the liver, the expression of CXCa, lysozyme G, β2-microglobulin and transferrin was significantly (P≤0.05) up-regulated in lice-infected fish with respect to control fish whereas expression of C3 was significantly (P ≤ 0.05) down-regulated in lice-infected fish. The expression of TLR 22-like, lysozyme C, TNFα genes was not detected in the liver samples of fish. This study indicates that majority of the genes showed down-regulation in kidney tissue whereas up-regulation in liver and skin tissues except C3 in Argulus-infected fish. We show that infection with this parasite irrespective of intensity can also result in immune gene expression changes in tissues situated away from the site of parasite attachment and feeding. The information obtained here could be useful towards understanding the susceptibility of rohu to argulosis and mechanisms involved in protection of rohu to ectoparasitic infections, which is causing immense economic losses to freshwater aquaculture sector. 相似文献
15.
Twenty-eight expressed sequence tags (ESTs) were isolated from a Nile tilapia (Oreochromis niloticus) vaccinated vs non-vaccinated subtractive library at 12-h post injection of a formalin killed Streptococcus iniae ARS-98-60 vaccine. The 28 ESTs were classified in terms of their putative functions. Half of the ESTs identified were unknown proteins. Of the remaining half ESTs, 17% have putative functions in protein biosynthesis and 11% have putative functions in immunity, energy production, and signal transduction, respectively. Immunity-related ESTs identified included high density lipoprotein-binding protein vigilin, immunoglobulin heavy chain, and QM-like protein. Quantitative PCR revealed that one EST (cytochrome c oxidase subunit II) was highly upregulated (1825 ± 336 fold) in vaccinated fish compared to that in non-vaccinated fish. Of the remaining 27 ESTs, nine were significantly (P<0.05) upregulated (<20 fold) in vaccinated fish. The nine significantly upregulated genes included five unknown or hypothetical proteins and four known proteins (high density lipoprotein-binding protein vigilin, QM-like protein, ribosomal protein S13, and ribosomal protein L5). The upregulation of these genes induced by killed S. iniae vaccines suggest that they might play important role in Nile tilapia defense against S. iniae infection. 相似文献
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Gun Wook Baeck Ji Hyung Kim Dennis Kaw Gomez Se Chang Park 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(1):53-58
Streptococcus sp. is gram-positive coccus that causes streptococcal infections in fish due to intensification of aquaculture and caused significant economic losses in fish farm industry. A streptococcal infection occurred from cultured diseased olive flounder (Paralichthys olivaceus) in May, 2005 at a fish farm in Jeju Island, Korea. The diseased flounder exhibited bilateral exophthalmic eyes and rotten gills; water temperature was 16~18℃ when samples were collected. Of the 22 fish samples collected, 3 samples were identified as Lactococcus garvieae and 18 samples were identified as Streptococcus parauberis by culture-based, biochemical test. Serological methods such as slide agglutination, hemolysis and antimicrobial susceptibility test were also used as well as multiplex PCR-based method to simultaneously detect and confirm the pathogens involved in the infection. S. parauberis and L. garvieae have a target region of 700 and 1100 bp., respectively. One fish sample was not identified because of the difference in the different biochemical and serological tests and was negative in PCR assay. In the present study, it showed that S. parauberis was the dominant species that caused streptococcosis in the cultured diseased flounder. 相似文献
18.
Chistiakov DA Hellemans B Volckaert FA 《Veterinary immunology and immunopathology》2007,117(1-2):1-16
European sea bass (Dicentrarchus labrax L.) is a marine species of great economic importance, particularly in Mediterranean aquaculture. However, numerous pathogenic viruses, bacteria, fungi and parasites affect the species, causing various infectious diseases and thereby leading to the most heavy losses in aquaculture production of sea bass. In this respect, knowledge on molecular and genetic mechanisms of resistance to pathogens and specific features of immune response against various infectious agents should greatly benefit the development of effective vaccines and proper vaccination strategies in marker-assisted selection of fish resistant to a range of infections. To date, genetic knowledge on sea bass immune regulatory genes responsible for resistance to pathogens is relatively poor but tends to accumulate rapidly. In this review, we summarize and update current knowledge on the immune system and immune regulatory genes of the sea bass. 相似文献
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多不饱和脂肪酸对鱼饲料转化率的影响及其机理 总被引：1，自引：0，他引：1
由于过分的海洋捕捞以及对海水鱼消费的增加,导致海水鱼油供不应求,研究使用鱼油替代品发展水产养殖业势在必行。植物油供应稳定,价廉物美,但是它富含多不饱和脂肪酸(PUFAs),却缺乏高度不饱和脂肪酸(HUFAs),尤其缺乏n-3HUFAs。文章结合本研究所多年来对HUFAs的研究成果,重点综述PUFAs特别是n-3HUFAs对鱼饲料转化率的影响及其机理,并探索植物油替代鱼油存在的问题及解决方法,以促进有效利用PUFAs和用植物油替代鱼油养殖海水鱼,发展可持续的海水养殖业。 相似文献