Prevalence of disease outbreak from cultured whiteleg shrimp Penaeus vannamei farms located in Karnataka, India

Abstract

Penaeus vannamei farming is one of the profitable businesses of the aquaculture sector in India. As a result of excessive farming, shrimps were susceptible to various exotic, transboundary, and emerging pathogens. The purpose of this study is to monitor the prevalence of shrimp pathogens in Karnataka. A total of 91 samples of P. vannamei post larvae and juveniles were collected from April 2022 to November 2022 in Karnataka. Samples were screened for pathogens as listed in Office of Internationale des Epizootics (OIE) or World Organisation for Animal Health (WOAH) which include infectious hypodermal and hematopoietic necrosis virus (IHHNV), Enterocytozoon hepatopenaei (EHP), acute hepatopancreatic necrosis disease (AHPND), hepatopancreatic parvovirus (HPV), infectious myonecrosis virus (IMNV), yellow head virus (YHV), taura syndrome virus (TSV), white spot syndrome virus (WSSV), and other diseases such as decapod iridescent virus-1(DIV-1), and monodon baculovirus (MBV). Out of 91 samples, 5 (5.5%) samples were positive for WSSV, 26 (28.6%) samples were positive for EHP, and 2 (2.2%) samples had co-infection caused by EHP and WSSV. In this study, we have reported a high prevalence of EHP than WSSV in all three coastal districts of Karnataka. Farmers were using specific pathogen-free (SPF) seeds for culture but still, their cultures are getting infected with the same pathogens which indicates poor pond preparation and bio-security. So we strongly recommend that farmers have to follow good management practices and bio-security to increase the productivity and sustainability of P. vannamei farming in India.