Department of Aquaculture and Seafood Technology, Faculty of Fisheries and Ocean Sciences, Ocean University, Sri Lanka
Abstract: (17 Views)
The escalation of shrimp aquaculture has been linked to frequent occurrences of bacterial (Vibrio spp.) and viral (white spot syndrome virus and infectious myonecrosis virus) illnesses that limit productivity and have traditionally resulted in significant antibiotic application. Due to their dependence on inherent cellular and humoral immunity, dietary immunomodulation has become a critical non-antibiotic approach for health management in penaeid shrimp. This analysis consolidates existing research on four primary categories of functional feed additives probiotics/symbiotic, prebiotics, β-glucans and associated immunostimulants, and phytogenic/herbal extracts along with their recorded impacts on immune metrics, gastrointestinal health, and survival rates post-pathogen exposure in Litopenaeus vannamei and Penaeus monodon. The examined literature indicates that additive supplementation is regularly linked to increased hemocyte activity, heightened expression of antimicrobial-peptide and pattern-recognition-receptor genes, augmented antioxidant enzyme activity, and better survival rates post-challenge, with combined (symbiotic or multi-additive) approaches often surpassing single-ingredient diets. The evaluation delineates the mechanistic pathways connecting gut microbiota modulation to systemic immune augmentation, encapsulates notable dose–response results, and addresses significant obstacles in standardization, strain/extract specificity, and field-scale validation that need resolution for the translation of laboratory discoveries into dependable commercial applications.