Primary diagnosis and surveillance of white spot syndrome virus in wild and farmed crawfish (Procambarus clarkii, P, zonangulus) in Louisiana, USA

• Published in: Diseases of aquatic organisms Vol. 85; no. 1; pp. 15 - 22
• Main Authors: BAUMGARTNER, W. A, HAWKE, J. P, BOWLES, K, VARNER, P. W, HASSON, K. W
• Format: Journal Article
• Language: English
• Published: Oldendorf Inter-Research 27.05.2009
• Subjects: Animal aquaculture; Animal productions; Animals; Animals, Domestic; Animals, Wild; Astacoidea - virology; Biological and medical sciences; Crustacea; Epithelium - pathology; Freshwater; Fundamental and applied biological sciences. Psychology; Invertebrate aquaculture; Invertebrates; Litopenaeus vannamei; Louisiana; Pathology; Polymerase Chain Reaction; Procambarus clarkii; White spot syndrome virus; White spot syndrome virus 1 - physiology; Louisiana; United States; North America; America; USA, Iowa; USA, Louisiana; Immunohistochemistry; Farming animal; White spot syndrome virus; Disease; Crawfish; First record; Wild animal; Crayfish; Macrura; Crustacea; Freshwater environment; Polymerase chain reaction; Procambarus zonangulus; Edible crustacean; Real-time PCR; Arthropoda; WSSV; Decapoda; Procambarus clarkii; Invertebrata; Sanitary surveillance; Comparative study
• ISSN: 0177-5103; 1616-1580
• DOI: 10.3354/dao02051

This is the first report of natural white spot syndrome virus (WSSV) infection in wild and large-scale farmed crawfish. In the spring of 2007, 3 crawfish farms experienced heavy mortality in ponds populated by Procambarus clarkii and P. zonangulus. Histological examination revealed findings consistent with severe viral infection characterized by numerous intranuclear inclusions in ectodermal and mesodermal tissues. Samples tested by in situ hybridization, injection bioassay in Litopenaeus vannamei, and PCR (nested and real time) were all positive for WSSV. Samples were sent to the National Veterinary Services Laboratory in Ames, Iowa, USA, where WSSV was verified. Subsequently, a multi-parish survey of 184 sites in Louisiana (including farm and wild basin samples) using real-time PCR determined that >60% of sites sampled were positive for WSSV, including wild basin samples.