Use of glycerol monolaurate as a treatment against white spot syndrome virus in crayfish (Procambarus clarkii)

Abstract

Glycerol monolaurate (GML), a monoester formed from glycerol and lauric acid, is widely used in food, cosmetics, and dietary supplements. GML also has antiviral activity against enveloped viruses. In this study, we conducted a challenge experiment to assess the effects of GML on the survival of crayfish (Procambarus clarkii) infected with white spot syndrome virus (WSSV). Dietary GML treatment reduced the mortality of WSSV-infected crayfish and reduced the WSSV copy number. Quantitative reverse transcriptase polymerase chain reaction analysis showed that GML enhanced the expression of immune-related genes, such as nuclear factor-κB and C-type lectin. GML increased three immune parameters (total hemocyte count, phenoloxidase activity, and superoxide dismutase activity) in crayfish with or without WSSV infection. GML also increased the hemocyte apoptosis rate in crayfish with or without WSSV infection. These data indicated that GML increased hemocyte apoptosis, THC, PO and SOD activity and reduced the mortality in crayfish after oral WSSV challenge, which suggested that GML can be used to keep the crayfish healthy.