Effect of Multi-Strain Probiotic Supplementation As Alternative to Antibiotics on Growth, Blood Biochemistry, Ileal Digestibility, Bacterial Growth, and Gut Histomorphology of Broiler Fed on Poultry Byproduct Meal

The study aimed to evaluate the effects of multi-strain probiotic (MSP) on broiler growth, health, and nutrient utilization under high animal protein concentrate conditions. Male Ross-308 broilers were assigned to four groups: a control (C), MSP at 50 mg/kg (MSP50), MSP at 100 mg/kg (MSP100), and Zinc bacitracin (ZB) as a positive control. MSP supplementation significantly improved feed intake, weight gain, and feed conversion efficiency, with MSP100 demonstrating the best feed conversion ratio during both starter and finisher phases. MSP also enhanced dressing percentages and positively influenced blood lipid profiles. The supplementation reduced harmful bacterial growth (E. coli, Salmonella, Clostridium perfringens) while promoting beneficial bacteria (Lactobacillus). Moreover, MSP positively impacted gut histomorphology, showing higher villus height, width, and crypt depth in the MSP100 group. Digestibility of dry matter and crude protein was enhanced in birds fed the MSP100 diet. Overall, MSP supplementation exhibited positive effects on broiler performance, health, and nutrient digestibility, indicating its potential as an antibiotic alternative for improving practices in the poultry feed industry.