Probiotic Zado® (Ruminococcus Flavefaciens) boosts hematology, immune, serum proteins, and growth profiles in Nile tilapia (Oreochromis niloticus)

Probiotics application in aquaculture could be a key solution to enhance the overall immune and growth indicators of cultured fish. Several bacteria have demonstrated encouraging results as probiotics for fish. The current study evaluated the possible effects of Zado® (Ruminococcus Flavefaciens 28 × 10⁴ CFU) dietary incorporation at 1 and 2 g/kg diet for 6-weeks on growth, hematological profile, immune performance, the biochemical, and anti-oxidative profiles of Oreochromis niloticus. Sampling was performed at the end of the third and sixth week. Fish fed with Zado® enriched diets showed (P < 0.05) significantly improved hematologic (MCHC, MCH, MCV, and PCV and RBCs count) and leukocytic readings (WBCs, monocytes and lymphocytes). The immune (phagocytosis, lysozyme U/ml, and nitric oxide pmol/ml) parameters were (P < 0.05) markedly increased in Zado® incorporated groups. Biochemical parameters (globulin, albumin and total proteins; AST and ALT) levels showed significant (P < 0.05) improvement at three and six weeks in Zado® groups. Serum glucose concentration was significantly higher in Zado® groups at three weeks, while was only higher for 2 g/kg Zado® at six weeks. Also, cortisol level was lower in both Zado® groups at three weeks, while was only lower for 1 g/kg Zado® at six weeks. In addition, antioxidants Gpx, SOD, and CAT were (P < 0.05) significantly higher in Zado® treatments, while pro-oxidant MDA was (P < 0.05) significantly decreased. Moreover, growth performance was also (P < 0.05) markedly boosted in Zado® incorporated groups compared to the control. Conclusively, our results demonstrated that Zado® probiotic is a safe alternative for O. niloticus with beneficial effects on hematological parameters, immune, biochemical, antioxidants, and growth profiles.