When olive flounders were fed for two weeks with
experimental diets containing varying concentrations of L. lactis (1 106, 5 106, 2.5 107 and
1.25 108 CFU/g feed), all the experimental feed groups showed 68e77% survival upon challenge with
S. iniae. A field-scale feeding trial with L. lactis dietary supplement was conducted in a local fish farm
(n ¼ 12,000) for three months, and disease resistance, innate immune parameters and growth performance
were evaluated. The average weight gain and feed efficiency were increased up to 6.8% and 8.5%,
respectively.