Diseases In Shrimp Aquaculture

Authors: Karuna Bamel

Abstract: Shrimp aquaculture in India is a major economic activity, with significant production and export values in 2019-2020. However, the industry is severely impacted by various diseases, including microbial infections and viral outbreaks. Key emerging diseases include White Faecal Syndrome (WFS), often linked to the microsporidian parasite Enterocytozoon hepatopenaei (EHP), and increased occurrences of White Spot Syndrome Virus (WSSV) and Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV). Vibrio species are prominent bacterial pathogens causing substantial economic losses, with transmission occurring through water, mucus surfaces, and the digestive tract. Other bacterial genera such as Erythrobacteraceae, Alteromonas, and Shewanella have also been isolated from shrimp ponds. Shewanella algae is of particular concern, with little information on its biochemical profiles and infection in aquaculture. Disease prevalence is influenced by water quality parameters like temperature, salinity, and pH, as well as factors such as increased stocking density and culture intensity. Histopathological studies show that pathogenic bacteria, such as Vibrio parahaemolyticus, rapidly target the hepatopancreas and intestinal epithelial cells of shrimp. Management strategies include the use of probiotics like Bacillus and lactic acid bacteria, which offer competitive exclusion, antiviral effects, and immune enhancement. Herbal extracts, such as those from Allium sativum and Thymus vulgaris, also demonstrate strong antibacterial properties. Other approaches include vaccination, bacteriophages, and immunostimulants. The presence of pathogenic bacteria in shrimp also poses a risk of seafood-borne illnesses to humans, underscoring the importance of proper refrigeration and monitoring from harvest to consumption.