Two Vibrio splendidus related strains collaborate to kill Crassostrea gigas: taxonomy and host alterations

Diseases of Aquatic Organisms

Frédérique Le Roux¹  Tristan Renault¹  Anne-Marie Pons¹  Mélanie Gay¹ 

关键词: Vibriosis;    Agonism;    Molecular taxonomy;    Histopathology;   

DOI  :  10.3354/dao062065

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: For several years, strains phenotypically related to Vibrio splendidus have been associated with mortality outbreaks of molluscs. A former study on Crassostrea gigas demonstrated the genetic diversity of V. splendidusstrains associated with diseased animals. Another study suggested that different strains may act in an additive/synergistic way leading to higher C. gigas mortality rates. Here, a strain pair (31+32) was characterised at taxonomic and virulencelevels. Using a polyphasic approach, these strains were confirmed to be V. splendidus-related, without a clear discrimination between V. kanaloae and V. pomeroyi since hybridisation rates with both these strains were above 70%.Following experimental infection of C. gigas by injection in the adductor muscle or in the pallial cavity, the host alterations induced were described. After injection of strains 31 and/or 32, bacteria were localised at the periphery of the muscleand induced extensive lesions of the translucent part of the adductor muscle. Muscle alterations were of 3 kinds: (1) presence of isolated rounded muscular fibres containing non-homogenous granular material and surrounded by a translucent halo; (2)presence of non-homogenous granular material in the cytoplasm of entire muscle bands; (3) affection of wide muscle areas with extremely condensed muscle fibres. Infiltration associated with these lesions was notably absent in the vast majority of theindividuals.

【 授权许可】

Unknown