PPIB and infection: Moreover, at day 10 post-treatment, fish were challenged with bacteria (Aeromonas hydrophila); the control group had early mortalities (2 vs. 4–5 days post-infection, respectively) and lower survival rate (60% vs. 80%, respectively) compared to fish fed with β-glucan for 15 or 30 days, and, interestingly, fish fed for 45 days with β-glucan had no mortality.