Selection of potential probiotic bacteria to use in fat snook (Centropomus parallelus Poey, 1860) culture

Abstract

The aim of this study was to isolate acid-lactic bacteria of the intestinal tract of fat snook and to evaluate its probiotic potential. Three bacterial strains were isolated, of which two inhibited the in vitro growth of Vibrio harveyi and V. alginolyticus. Of these strains, the one that presented larger in vitro growth (Lactococcus sp.) was used in the in vivo assay, using Lactobacillus plantarum, already used as probiotic in shrimps, as comparative. These two strains of acid-lactic bacteria colonized the intestinal tract of the fry of fat snook at concentrations of 1.10 ± 0.8 x 10⁵ CFU g^-1 for Lactococcus sp. and 1.96 ± 0.14 x 10⁴ CFU g^-1 for L. plantarum. The snooks fed with feed supplemented with Lactococcus sp. (1.09 ± 0.19 x 10⁴ CFU g^-1) and L. planaturm (2.45 ± 0.30 x 10³ CFU g^-1) presented in the intestinal tract a population of Vibrio spp. inferior to the control (7 x 10⁶ CFU g^-1).