Immunomodulatory activity of plants against white spot syndrome virus (WSSV) in shrimp culture: a review

Disease outbreaks in shrimp have increased as the global shrimp aquaculture industry has become more intensive. The white spot syndrome virus (WSSV) is a highly virulent and lethal infection that causes the most harm to global penaeid shrimp production, with a massive mortality rate of 80 to 100% within 3 to 10 days of the onset of clinical symptoms. As there is no effective treatment for the disease, numerous control or management measures have been implemented to eradicate the virus. Plants can serve as an eco-friendly alternative to antibiotics or as immunostimulants for shrimp against WSSV with significant enhancement of immune parameters. This review focuses on terrestrial and marine plants/algae that can stimulate shrimp immunity against WSSV, screening of plant extracts against WSSV, and various plant forms (powder, crude extract, fraction, and their compounds) that can inhibit WSSV infection in shrimp by increasing their immune response. The Sargassaceae family has been reported as an immunostimulant against WSSV the most frequently, followed by the Gracilariaceae, Poaceae, and Leguminosae families. Further studies are necessary to identify the active compounds and to apply them on a large scale in shrimp aquaculture.