Survival, Immune Response and Gut Microbiota in Litopenaeus vannamei Fed Synbiotics, Paraprobiotics, and Postbiotics and Challenged with Vibrio parahaemolyticus

The effect of bacterial additives on immune response, intestinal microbiota, and survival of the white shrimp Litopenaeus vannamei was evaluated. Bacillus licheniformis BCR 4-3 and Vibrio parahaemolyticus IPNGS16 cultures were spray-dried. Inulin, probiotics, and postbiotics of Bacillus (SPB) and postbiotics of Vibrio (PVp) were added to the commercial feed. An experiment with three treatments in triplicate was performed during 19 days. The growth was not affected by the additives but survival of animals was significantly higher as compared to control group. The expression of SOD, crustin, and penaeidin4 in PVp-treated animals was significantly higher compared to the control but lysozyme expression did not change. The phyla, families, and genera that predominated in the white shrimp intestine were Proteobacteria, Bacteroidetes, Rhodobacteraceae, Vibrionaceae, Pseudoalteromonadaceae, Vibrio, Ruegeria, and Phaeobacter. The Vibrio genus decreased significantly in SPB and PVp treatments, compared to the control. The control, SPB, and PVp shared 294 OTUs. No changes were observed in the alpha and beta diversity. The metabolic activity of Vibrio and Roseobacter was higher in the control compared to SPB and PVp, whereas for Phaeobacter and Ruegeria, it decreased. Feed additives increase survival and modulated the immune response and gut microbiota of the white shrimp, so they can be used in commercial farms to increase production.