DAO 71:175-178 (2006)  -  doi:10.3354/dao071175

ABSTRACT: The effect of hyperthermia on the development of white spot syndrome virus (WSSV) in the crayfish Procambarus clarkii was studied by competitive PCR. Crayfish were exposed to different temperatures (24 ± 1 and 32 ± 1°C) after WSSV injection. No mortality was observed when crayfish were held at 32 ± 1°C, but mortality reached 100% when crayfish were transferred to 24 ± 1°C. Competitive PCR showed that viral levels at 32 ± 1°C remained at 10⁵ copies mg^–1 tissue, while at 24 ± 1°C levels were significantly higher, rising from 10⁴ to 10¹⁰ copies mg^–1 tissue. These results suggest that hyperthermia reduces viral replication, but does not eliminate viral particles from WSSV-infected crayfish.

KEY WORDS: White spot syndrome virus · Hyperthermia · Viral replication · Procambarus clarkii · Competitive PCR · Water temperature