Abstract
The present study investigated the impact of dietary papaya leaf meal (PLM) at three inclusion levels (0%, 6%, and 12%) with or without multi-enzyme supplementation (0.5 g/kg diet) on growth performance, nutrient digestibility, carcass characteristics, serum biochemistry, lipid profile, and antioxidant status in Arbor Acres broiler chickens. A total of 240 one-day-old chicks were allocated to six treatments in a 3 × 2 factorial arrangement for 42 days. Enzyme supplementation significantly improved body weight gain, feed conversion ratio, and nutrient efficiency (p < 0.001), while moderate PLM inclusion (6%) supported optimal performance. Digestibility of crude fiber and ether extract was enhanced by enzymes (p < 0.05), with a notable PLM × enzyme interaction for fiber digestibility. Carcass yield was unaffected, but enzyme supplementation increased dressing percentage and reduced abdominal fat. Serum biochemistry remained largely unchanged, except for elevated AST at 12% PLM (p < 0.01). Lipid profile improved with enzyme supplementation, reducing total cholesterol, triglycerides, and LDL while increasing HDL (p < 0.05). Enzyme supplementation significantly increased SOD and CAT activities (p < 0.001), whereas TAC responses were inconsistent across treatments. Lipid peroxidation (MDA) increased at 12% PLM, indicating a potential oxidative imbalance at higher inclusion levels. In conclusion, multi-enzyme supplementation was the primary driver of growth performance and nutrient utilization improvements, while moderate PLM inclusion (6%) exerted supportive and synergistic effects without compromising carcass traits.