SYNLAC Prime probiotics alleviate Enterocytozoon hepatopenaei-induced damage in white shrimp, Penaeus vannamei by enhancing growth, immunity, and resistance to Vibrio parahaemolyticus

Abstract

This study evaluates the efficacy of SYNLAC Prime probiotics, both live and heat-killed, in alleviating growth retardation and enhancing the health of white shrimp, Penaeus vannamei infected with Enterocytozoon hepatopenaei (EHP). Probiotic supplementation significantly improved growth performance of EHP-infected shrimp by increasing digestive enzyme activity in the hepatopancreas and guts. Interestingly, the final weight and weight gain percentage of EHP-infected shrimp supplemented with live probiotics surpassed that of healthy control shrimp. Probiotics modulated the gut microbiota, notably reducing Vibrio abundance. The immunomodulatory effects of probiotics were further highlighted by increased expression of immune-related genes and enhanced immune parameters. These immune responses are critical for pathogen defense and may contribute to the observed reduction in EHP load and increased resistance to Vibrio parahaemolyticus infection. To elucidate the metabolic differences between healthy and EHP-infected shrimp and to assess the effects of dietary probiotic supplementation, hepatopancreatic metabolite profiles were analyzed using LC-MS/MS. In positive ion mode, 54, 76, and 84 differential metabolites were identified in the NCON, P5D, and P5L groups, respectively, relative to the PCON group. In negative ion mode, 89, 80, and 64 metabolites were significantly altered across the same comparisons. KEGG pathway enrichment indicated that differential metabolites were primarily involved in key metabolic pathways, including terpenoid backbone biosynthesis, one-carbon metabolism, glycolysis/gluconeogenesis, pyrimidine metabolism, and amino acid biosynthesis. Notably, probiotic supplementation modulated multiple metabolic pathways associated with host immunity and energy metabolism. Heatmap analyses further revealed distinct metabolite expression patterns across all experimental groups. Overall, the findings demonstrate that probiotics, particularly live strains, offer a promising intervention for mitigating EHP-induced growth impairment and disease, enhancing both immune responses and metabolic stability in shrimp. This highlights the potential of probiotics as an effective tool in shrimp aquaculture, not only to improve growth performance but also to manage infections and improve overall health.

Keywords: Alleviation; Enterocytozoon hepatopenaei; Metabolic analysis; Probiotic; White shrimp.