In-water Bacillus species probiotic improved water quality, growth, hemato-biochemical profile, immune regulatory genes and resistance of Nile tilapia to Aspergillus flavus infection

Fish farming practices currently make effective use of probiotic Bacillus species, specifically Bacillus subtilis and B. licheniformis. The current study assessed the water quality, growth performance, body composition, hemato-biochemical activities, immune regulatory genes, and resistance to Aspergillus flavus in order to determine the effectiveness of the water additive probiotic Bacillus species mixture (SANOLIFE®PRO-W) on Nile tilapia aquaculture. Fish were kept in four groups (control, 0.01, 0.02, 0.03) gm. /m3for 56 days using Bacillus species in-water treatment. The results showed that the fish treated with SANOLIFE® performed significantly better (P < 0.05) in terms of growth. Significant (P < 0.05) improvements were also observed in the immune regulatory genes, antioxidant capacity, and haemato-biochemical parameters. A. flavus challenged fish showed significantly (P < 0.05) lower mortalities, indicating that Bacillus species probiotic enhanced the fish's innate immune response. In order to improve water quality, fish growth, and antioxidant activities together with innate the immune responses, Bacillus species mixture (SANOLIFE®PRO-W) can be recommended to be used in Nile tilapia aquaculture.