A Broad-Host-Range Phage Cocktail Selectively and Effectively Eliminates Vibrio Species from Shrimp Aquaculture Environment

The protective effects of a phage cocktail composed of vB_Vc_SrVc2 and vB_Vc_SrVc9 were tested in Pacific white shrimp (Litopenaeus vannamei) postlarvae, which were originally isolated from diseased shrimps and selected due to their broad-host-range properties against several pathogenic Vibsrio species. We used culture-dependent and culture-independent approaches to explore its effect on bacterial communities associated with shrimp postlarvae. Both methods revealed that the levels of Vibrio species were significantly reduced after phage cocktail administration. Phage-treated shrimp also exhibisuppted lesser damage and higher lipid accumulation in B cells of the hepatopancreas, as revealed by histopathological examination. Taken together, this study provides clear evidence that phage therapy can selectively and effectively reduce Vibrio species, thereby providing an environmentally safe alternative to the prophylactic use of antibiotics in shrimp aquaculture.