DAO 120:143-150 (2016)  -  DOI: https://doi.org/10.3354/dao03018

Experimental inoculation of Louisiana red swamp crayfish Procambarus clarkii with white spot syndrome virus (WSSV)

Barcley T. Pace1, John P. Hawke2, Ramesh Subramanian3, Christopher C. Green1,*

1Louisiana State University Agricultural Center, Aquaculture Research Station, Baton Rouge, Louisiana 70820, USA
2Louisiana State University School of Veterinary Medicine, Department of Pathobiological Sciences, Baton Rouge, Louisiana 70803, USA
3Louisiana State University School of Veterinary Medicine, Division of Biotechnology & Molecular Medicine, Baton Rouge, Louisiana 70803, USA
*Corresponding author:

ABSTRACT: The red swamp crayfish Procambarus clarkii represents an important aquaculture species responsible for over half of all commercial aquaculture profits in Louisiana, USA. White spot syndrome virus (WSSV) is highly pathogenic in crustacean species and induces mass mortality in aquaculture operations worldwide. Natural outbreaks of WSSV occur yearly in cultured populations of crayfish in Louisiana. The goal of this study was to better understand the infectivity of WSSV in P. clarkii, by determining the minimum lethal dose necessary to initiate infection and to measure the resulting cumulative mortality following infection with different doses. A real time quantitative PCR (qPCR) method was used to detect WSSV in DNA extracted from gill tissue to ensure P. clarkii study populations were WSSV-free before the start of trials. Viable viral particles were isolated from naturally infected P. clarkii gill tissue and quantified using a novel digital PCR approach. Three infectivity trials were performed, and WSSV inocula were created by serial dilution, generating 5 treatments per trial. Five crayfish (weighing ~25 g) per dilution per trial received viral inoculations. Mortality was monitored daily for the duration of the trial in order to construct a median lethal dose (LD50) curve, and probit regression analysis was used to determine LD50 concentrations of viral particles. Knowledge of the infectivity of WSSV in native crayfish populations is of critical importance to the management of the commercial crayfish aquaculture industry in Louisiana. This is the first study to investigate the infectivity and to determine the LD50 of the Louisiana strain of WSSV in native crayfish.


KEY WORDS: Nimaviridae · Whispovirus · Crustacean · Aquaculture · LD50


Full text in pdf format 
Cite this article as: Pace BT, Hawke JP, Subramanian R, Green CC (2016) Experimental inoculation of Louisiana red swamp crayfish Procambarus clarkii with white spot syndrome virus (WSSV). Dis Aquat Org 120:143-150. https://doi.org/10.3354/dao03018

Export citation
Mail this link - Contents Mailing Lists - RSS
- -