Starter phase broiler response to <i>Moringa oleifera</i> leaf meal, a three-strain <i>Bacillus</i> probiotic, or butyric organic acid as alternatives to antibiotic growth promoters

This study investigated the effects of replacing in-feed AGPs with either Moringa oleifera leaf meal (MOLM), a three-strain Bacillus probiotic, or a coated butyric acid on the growth performance, digestive organ size and intestinal morphology of broiler chicks during the starter phase (0–14 days). Day-old, mixed-sex Cobb 500 broiler chicks (n = 300) were randomly allocated to experimental pelleted basal starter diets containing (1) 300 g/ton zinc bacitracin and 500 g/ton salinomycin (positive control; PC), (2) 1000 g/ton MOLM, (3) 500 g/ton three-strain Bacillus probiotic (PROB), (4) 1000 g/ton coated butyric acid (ORGA) and (5) no additives (negative control; NC). At d7 and d14, PC birds had higher bodyweights and FCR, followed by ORGA and PROB fed birds. MOLM fed birds had the heaviest small intestines (p < 0.05), while the NC group had the lightest; with heaviest (p < 0.05; 9.67) caecum in both the MOLM and NC birds compared to those in the PC (9.33), ORGA (7.00) and PROB (7.00). Jejunal villi length was significantly longer (p < 0.05) in the NC birds (511.37) then MOLM (505) and PC had the shortest (348.75). The three AGP alternatives tested showed optimum response in production parameters and beneficial effects on intestinal development, highlighting their potential as a functional feed additive in early broiler growth. Additionally, with high hygienic-biosecurity standards, NC treatment can be just as effective.