Thirty lactic acid bacteria (LAB) isolates were obtained from the digestive tracts of whiteleg shrimp ( Penaeus vannamei ) and screened for antagonistic activity against Vibrio parahaemolyticus , the causative agent of Acute Hepatopancreatic Necrosis Disease (AHPND). Among these, four isolates demonstrated strong inhibitory effects, producing inhibition zones of 16–20 mm in agar well diffusion assays. These four LAB isolates w...