Abstract
Abstract The growing pressure and irreversible process of reducing and eliminating the use of antibiotic growth promoters (AGP) has stirred research towards development of phytogenic feed additives (PFA) as future alternatives for profitability and sustainability of poultry enterprises. The experiment aimed to compare the effects phytogenic Moringa oleifera leaf powder (MO) vs antibiotic growth promoter on growth performance, carcass characteristics, lymphoid organ indices, intestinal lesions, bloody excreta, microbial population, mortality, and economic viability of broiler chicken. Day-old Cobb-500 (n = 1600) unsexed chicks were allotted 16 pens and randomly assigned to a control standard basal diet group containing antibiotic growth promoters zinc bacitracin (486 mg) and salinomycin (650 mg per kg of feed) (CON) or a basal diet + 1% MO (MO1) or a basal + 3.0% MO (MO3), or basal diet + 5% MO (MO5) in a completely randomised design. The experiment lasted for 35 days. Supplementation with MO in diets significantly decreased ADFI, ADG, and FCR (P < 0.05) during the starter, grower, and finisher phases. The highest ADFI and ADG (P < 0.05) for the whole phase (d 1–35) was recorded in the control group, whilst the lowest was observed for in MO5. Feed conversion rate was highest (P < 0.05) in birds on MO1 diets during starter, grower, as well as the overall period whilst the lowest was noted for MO5 group. There was no significant effect of MO on breast, thigh and heart proportions (P < 0.05). The mean proportions of drumstick, wing, feet, neck, small intestine, liver, and gizzard (P < 0.05) improved with MO supplementation. The highest (P < 0.05) abdominal fat was observed in the control group. The spleen, Bursa of Fabricius, liver and intestine indices were highest in birds on MO5 group and comparable among other groups. Results show a reduction in necrotic scores with an increase in dietary MO levels. The control group and birds receiving 5% MO in diets recorded the least bloody excreta scores among all treatment groups (P < 0.05). Incremental levels of MO led to reduced total aerobic bacteria, E. coli, C. perfringens and increase lactobacillus spp. counts in all intestinal segments. Overall total cost of feed per bird was highest in birds in 5% MO (39.97) followed by 3% MO (30.58) and 1% MO (20.90) and lowest in CON (20.42). The CON group obtained the highest gross and net revenue per bird, whereas birds fed 5% MO recorded losses per bird. The highest economic efficiency (1,14) was achieved in birds on CON diets, and lowest in MO5 group (− 0.11) birds. Moringa oleifera leaf meal can be offered at 1–3% as an alternative to antibiotics for better feed conversion ratios, reduced abdominal fat, improved immune indicators, gut microbiota populations and low mortality. The high cost of MO reduces the economic efficiency and thus cheaper sources are necessary for sustainable small-scale communal and commercial enterprises.