Shewanella putrefaciens in cultured tilapia detected by a new calcein-loop-mediated isothermal amplification (Ca-LAMP) method.
Dis Aquat Organ
; 117(2): 133-43, 2015 Dec 09.
Article
em En
| MEDLINE
| ID: mdl-26648105
ABSTRACT
Shewanella putrefaciens is being increasingly isolated from a wide variety of sources and is pathogenic to many marine and freshwater fish. For better control of this pathogen, there is a need for the development of simple and inexpensive but highly specific, sensitive, and rapid detection methods suitable for application in field laboratories. Our colorogenic loop-mediated isothermal amplification (LAMP) assay combined with calcein (Ca-LAMP) for unaided visual confirmation of LAMP amplicons is a simple method for fish pathogen detection in cultured tilapia. Here, we describe the detection of S. putrefaciens using the same platform. As before, the method gave positive results (orange to green color change) in 45 min at 63°C with sensitivity 100 times higher than that of a conventional PCR assay, with no cross-amplification of other known fish bacterial pathogens tested. Using the assay with 389 samples of gonads, fertilized eggs, and fry of farmed Nile and red tilapia Oreochromis spp., 35% of samples were positive for S. putrefaciens. The highest prevalence was found in samples of gonads (55%) and fertilized eggs (55%) from adult breeding stocks, indicating that S. putrefaciens could be passed on easily to fry used for stocking production ponds. Tissue tropism assays revealed that the spleen showed the highest colonization by S. putrefaciens in naturally infected tilapia and that it would be the most suitable organ for screening and monitoring fish stocks for presence of the bacteria.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Infecções por Bactérias Gram-Negativas
/
Tilápia
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Shewanella putrefaciens
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Técnicas de Amplificação de Ácido Nucleico
/
Doenças dos Peixes
Tipo de estudo:
Diagnostic_studies
/
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Dis Aquat Organ
Assunto da revista:
BIOLOGIA
/
MEDICINA VETERINARIA
/
MICROBIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Tailândia