Effect of intestinal autochthonous Enterococcus faecalis on the growth performance, gut morphology of Malaysian mahseer (Tor tambroides) and protection against Aeromonas hydrophila

Abstract The study aimed to investigate the effects of dietary supplementation of two strains of potential intestinal autochthonous probiotics, Enterococcus faecalis on growth performances, body composition, gut morphology of Malaysian mahseer, Tor tambroides, and survival of the juveniles challenged with Aeromonas hydrophila. In this study, 270 fish were fed for 70 days with three different diets; a control (CON) and two diets supplemented with E. faecalis (1x108 CFUg-1) as strains 2674 (T1) and FC11682 (T2). At the end of the study, growth performance, whole body fatty acid profiles, and gut morphology (villus length, width, and villus area) were significantly (P <0.05) increased in probiotic treatment groups. The highest (P <0.05) weight gain (%), SGR (% day -1), and FCR were observed in T2. Additionally, the mortality after challenge test was 100% in the control group (CON) whereas values were the lowest (30%) (P <0.05) in T2 followed by T1 (40%). Both the T1 and T2 showed significantly improved growth, gut morphology, and protection against A. hydrophila, with E. faecalis strain FC11682 (T2) being the most recommended of tested probiotics for Malaysian mahseer.