Comparative effect of exogenous protease and phytobiotics on growth performance, nutrient digestibility, ileal histology and bone strength in broilers

A total of 540 d-old Cobb 500 broiler chickens were randomly allocated into five groups: a control group receiving only the basal die (control), and experimental groups supplemented with exogenous protease (30,000 IU/kg) and crushed seeds of Bunium persicum, Coriandrum sativum, and Carum copticum (10 mg/kg each) for a period of 35 days. The results demonstrated that growth performance parameters, including feed intake, weight gain, and feed conversion ratio, were significantly improved (P < 0.05) in broilers supplemented with protease compared to those receiving the selected herbs. Additionally, the digestibility of crude protein and crude fat showed a significant increase (P < 0.05) in broilers that received protease compared to the Bunium persicum. Tibia bone weight significantly improved (P = 0.01) in birds supplemented with protease, Coriandrum sativum and Carum copticum. In addition, the robusticity index decreased (P < 0.05) in protease supplemented group. In terms of ileal histological features increased (P < 0.05) in broilers supplemented with protease compared to the control. In summary, the results indicate that protease supplementation yielded superior outcomes in terms of improving growth, ileal digestibility, bone quality, and villus dimensions in broilers compared to the herbal plant supplements used in this study.