Improved growth rate and disease resistance in olive flounder, Paralichthys olivaceus, by probiotic Lactococcus lactis WFLU12 isolated from wild marine fish

In this study, host-derived probiotic strain outperforms elimination of pathogen through competitive exclusion in the gastrointestinal tract and increased innate immune responses. More importantly, this promising probiotic strain significantly promoted fish growth along with better feed conversion. This study will provide insight into how optimal probiotics should be selected and developed. It might facilitate the replacement of commercial fish probiotic products originated from terrestrial sources with host-derived probiotics in the near future.