Potential effects of probiotics (immunobacteryne; IMB) on growth performance, feed efficacy, blood biochemical, redox balance, nonspecific immunityand heat-shock protein expression of Nile tilapia (Oreochromis niloticus) fingerlings.

Abstract

The supplementation of aquafeed with probiotics is recommended for feasible aquaculture activities. Therefore, the aim of current study was to investigate the potential effects of probiotics on growth performance, feed utilization, biochemical attributes, redox statusand immunity response as well as the transcription of heat-shock protein 70 (HSP70)and insulin-like growth factor-1 (IGF-1) genes of Nile tilapia (Oreochromis niloticus; n = 120). Fish with an initial weight of 8.17 ± 0.02 g/fish wererandomly divided into four treatment groups and were fed diets containing 0, 0.5, 1and 1.5 mg immunobacteryne (IMB)/kg dietrespectively. Dietary IMB at 1.5 g/kg diet significantly improved the growth performance, feed consumptionand growth hormonesecretion of the experimental fish (p < 0.05). The 1 or 1.5 g IMB/kg diet boosted phagocytic activities and innate immune response. Serum total protein, total cholesterol, triglyceridesand glucose were significantly increased in the groups that were fed 1 and 1.5 mg IMB/kg diet compared to the control (p < 0.05). Meanwhile, the levels of uric acid, creatinine, liver enzymes (aspartate transaminase and alanine transaminase)and cortisol hormone were significantly reduced in the aforementioned treated groups compared to the control (p < 0.05). All fish fed IMB-supplemented diet showed a significant increase in the expression of IGF-1 gene, while the transcription of HSP70 was significantly decreased (p < 0.05). In conclusion, the dietary inclusion of IMB (1 g/kg diet) enhanced growth promoters, feed efficacy, blood biochemical, redox balanceand nonspecific immune responses in Nile tilapia fingerlings.