Impact of probiotic <i>Bacillus</i> sp. dietary supplementation on pancreatic and intestinal activities in seabream <i>Sparus aurata</i>

The main objective of this study was to investigate the effects of commercial probiotic Bacillus sp. supplementation on seabream Sparus aurata larviculture under culture conditions. In this context, Bacillus was supplemented via rotifer feeding and water and its effects on pancreatic and intestinal enzyme activities as well as aquaculture parameters were evaluated during early life development. In the experimental group, as probiotic three Bacillus sp. spores were introduced via rotifer and larval culture tanks, while the larvae in control group did not feed any probiotic supplementation. At the end of the experiment on 40 days after hatching, the probiotic-supplemented group exhibited better growth performance and there were statistically differences in between groups of probiotic-treated and control regarding growth parameters (P < 0.01), despite insignificant survival rate (P > 0.05). In terms of enzymatic expressions, S. aurata larvae receiving probiotic supplementation through rotifers demonstrated noteworthy (P < 0.05) enhancements in specific activities of pancreatic and intestinal enzymes, except for amylase (P > 0.05), when compared to the control group. It is concluded that the administration of Bacillus sp. as probiotic bacteria through rotifer supplementation and water intake demonstrates significant positive impacts on both growth parameters and specific activities of main pancreatic and intestinal enzymes of seabream larvae.