Dietary Perilla frutescens modulates host defense and reshapes stomach microbiota against AHPND in black tiger shrimp (Penaeus monodon)

Shrimp aquaculture is part of global seafood production, but recurring disease outbreaks threaten its sustainability and productivity. Acute hepatopancreatic necrosis disease (AHPND), caused by Vibrio parahaemolyticus strains harboring PirAB vp toxins, remains one of the most devastating bacterial diseases in shrimp farming. In this study, we evaluated the potential of Perilla frutescens powder (PP), a phytogenic feed additive enriched in rosmarinic acid and flavonoids, as a functional dietary intervention against AHPND. Black tiger shrimp ( Penaeus monodon ) were fed diets supplemented with 0.5 or 1% PP for 14 days, followed by challenge with an AHPND-causing V. parahaemolyticus strain. Dietary PP significantly reduced mortality, bacterial loads, and PirAB vp toxins in infected shrimp. The 1% PP group had enhanced immune and antioxidant responses, including activation of the proPO system, increased superoxide dismutase activity, and improved regulation of reactive oxygen species. Histopathological analyses showed reduced tissue damage following infection. In addition, stomach microbiota profiling revealed community shifts characterized by a reduction in Vibrionaceae (including Vibrio ) and enrichment of beneficial taxa such as Flavobacteriaceae and Pseudoalteromonadaceae . These findings demonstrated that dietary PP supplementation enhanced immune competence, modulated stomach microbiota, and mitigated AHPND-associated pathology, supporting its potential as a sustainable functional feed strategy in shrimp aquaculture.