Herpes virus in juvenile Pacific oysters Crassostrea gigas from Tomales Bay, California, coincides with summer mortality episodes

Diseases of Aquatic Organisms

Eugene M. Burreson¹  Ralph A. Elston¹  Kimberly S.Reece¹  Bruce J. Barber¹  Carolyn S. Friedman¹  Colleen A. Burge¹  John S. Hargove¹  Robyn M. Estes¹  Nancy A. Stokes¹ 

关键词: Pacific oyster;    Herpes virus;    Mortality;    Tomales Bay;    California;   

DOI  :  10.3354/dao063033

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Pacific Crassostrea gigas and eastern C. virginica oysters were examined between June 2002 and April 2003 from 8 locations along the east, west and south USA coasts for oyster herpes virus (OsHV) infections using the A primer setin a previously developed PCR test. Only surviving Pacific oysters from a mortality event in Tomales Bay, California, USA, where annual losses of oysters have occurred each summer since 1993, were infected with a herpes-like virus in 2002. PCR examinationusing template amounts of both 50 and 500 ng were essential for OsHV detection. Sequence analysis indicated that the Tomales Bay OsHV was similar to that identified in France with the exception of a single base pair substitution in a 917 bp fragment ofthe viral genome. However, unlike the French OsHV-1, the Tomales Bay OsHV did not amplify with the primer pair of a second OsHV-1 PCR assay, suggesting that further characterization of these viruses is warranted. No evidence of Cowdry type A viralinfections characteristic of herpes virus infections or other pathogens were observed in OsHV-infected oysters. Hemocytosis, diapedesis and hemocyte degeneration characterized by nuclear pycnosis and fragmentation were observed in infected oysters, whichis consistent with previous observations of OsHV infections in France. Together these data suggest that OsHV may be associated with the annual summer Pacific oyster seed mortality observed in Tomales Bay but establishment of a causal relationship warrantsfurther investigation.

【 授权许可】

Unknown