Potential Impacts of Dietary Bacillus licheniformis Inclusion on Growth Performance, Serum Metabolites, Antioxidant Profiles and Immune Status of Broiler Chickens

Background: Probiotics have become increasingly important in poultry industry due to their potential beneficial impacts on improved gut health, enhanced growth performance and boosted immune system. Methods: One hundred and sixty one day old Ross308 broiler chicks were allocated at random into four groups, with each group having four replicates of ten chicks. The groups were fed a basal diet containing Bacillus licheniformis (B. licheniformis) probiotic at concentrations of 0, 250, 500 and 1000 mg/kg feed. Feed intake (g), feed conversion (g/g) and body weight gain (g) were recorded. Dressing percentage and goblets parts were recorded upon slaughtering of control and B. licheniformis groups. Blood samples were centrifuged for serum collection and further analyses of antioxidant and metabolites profiles. Additionally, the antibody titer of the humral immune response against the Newcastle virus vaccine was evaluated using the ELISA test. Result: The results of the current study showed that dietary probiotic B. licheniformis consumption improved (P less than 0.001) feed intake, feed conversion ratio and body weight gain. Dressing and goblets percentage remained unaffected by the dietary probiotic B. licheniformis incorporation if compared to control. Serum antioxidant and metabolites profiles were improved with the probiotic B. licheniformis incorporation. Additionally, significant differences between control, 250 B. licheniformis, 500 B. licheniformis groups compared to 1000 B. licheniformis group on antibody titer (p less than 0.05) against Newcastle. It could be concluded that adding 250 or 500 mg/kg of B. licheniformis probiotic to the feed significantly boosted broiler chick growth, improved their metabolic function and enhanced their antioxidant capabilities.