Arbitrarily primed PCR to type Vibrio spp. Pathogenic for shrimp Auteur(s) : Goarant, Cyrille Merien, F Berthe, Franck Mermoud, I Perolat, P Éditeur(s) : Amer Soc Microbiology Résumé : A molecular typing study on Vibrio strains implicated in shrimp disease outbreaks in New Caledonia and Japan was conducted by using AP-PCR (arbitrarily primed PCR). It allowed rapid identification of isolates at the genospecies level and studies of infraspecific population structures of epidemiological interest. Clusters identified within the species Vibrio penaeicida were related to their area of origin, allowing discrimination between Japanese and New Caledonian isolates, as well as between those from two different bays in New Caledonia separated by only 50 km. Other subclusters of New Caledonian V. penaeicida isolates could be identified, but it was not possible to link those differences to accurate epidemiological features. This contribution of AP-PCR to the study of vibriosis in penaeid shrimps demonstrates its high discriminating power and the relevance of the epidemiological information provided. This approach would contribute to better knowledge of the ecology of Vibrio spp. and their implication in shrimp disease in aquaculture. Applied And Environmental Microbiology (0099-2240) (Amer Soc Microbiology), 1999-03 , Vol. 65 , N. 3 , P. 1145-1151 Droits : American society for microbiology http://archimer.ifremer.fr/doc/1999/publication-2734.pdf http://archimer.ifremer.fr/doc/00000/2734/ | Partager |
Quantification of Vibrio penaeicida, the etiological agent of Syndrome 93 in New Caledonian shrimp, by real-time PCR using SYBR Green I chemistry Auteur(s) : Goarant, Cyrille Merien, F Éditeur(s) : Elsevier Résumé : Shrimp farming is a small but growing industry in New Caledonia. Since 1993, "Syndrome 93" has been affecting New Caledonian shrimp farming industry every cold season, causing severe epizootic mortalities in grow-out ponds and significant losses. Highly pathogenic strains of Vibrio penaeicida are considered the etiological agent of the disease in Litopenaeus stylirostris. On one hand, studies demonstrated that healthy shrimp may carry V penaeicida for weeks with a high overall prevalence, regardless of any seasonal pattern or temperature conditions. On the other hand, larvae are free of V penaeicida and are also resistant to experimental infection. V penaeicida is frequently detected in incoming water pumped from the bays, which was shown, by a molecular typing study, to be the infectious source. This particular epidemiological pattern highlights the major role of the factors that trigger and aggravate the disease in grow-out ponds, where shrimp populations carry the pathogen all year round. In order to gain a better understanding of "Syndrome 93" epidemiology, quantification of V penaeicida both in shrimp and the shrimp farm ecosystem is necessary. This article describes the steps in the successful development of a real-time PCR quantification assay of V penaeicida in shrimp haemolymph, seawater (from ponds or bays) and sediment pore water, including the choice of an accurate extraction technique. The entire detection method; including sample processing, DNA extraction and real-time PCR amplification, can be completed within 4 h. (c) 2006 Elsevier B.V All rights reserved. Journal of Microbiological Methods (0167-7012) (Elsevier), 2006-10 , Vol. 67 , N. 1 , P. 27-35 Droits : 2006 Elsevier http://archimer.ifremer.fr/doc/2006/publication-1903.pdf DOI:10.1016/j.mimet.2006.02.013 http://archimer.ifremer.fr/doc/00000/1903/ | Partager |