Effects of Bacillus probiotic enzyme extract on growth and carcass biochemical composition of rainbow trout (Oncorhynchus mykiss) larvae

The present study was done to evaluate the effects of enzyme extract, produced by five species of probiotics Bacillus on growth and carcass biochemical composition of rainbow trout (Oncorhynchusmykiss) larvae with initial body weight of 0.583 ± 0.197 g (mean ± SD) . The enzyme extract was produced by Bacillus probiotics in broth media with concentrations of 1 × 106, 1 × 107 and 1 × 108 CFU/100g and then it was added into the feed of rainbow trout larvae respectively. The results of larval biometry at the end of the study showed that the use of enzyme extract with the highest Bacillus concentration (1×108 CFU/100g) in T3 (20.02 ±3.77 g) significantly increased the growth (P