Bahri Syamsuryadi, Eko Widodo, Lilik Eka Radiati, Suyadi Suyadi
This study aimed to evaluate the interaction effects between initial body weight of day-old broiler chicks (DOC) and dietary antioxidant supplementation (Vitamin E (VE), Selenium (Se), and their combination) on physiological responses, growth performance, hematological profile, and intestinal morphology. A 3×3 factorial completely randomized design was used, involving 288 Cobb 500 broilers grouped by DOC weight (light: 29–33 g, medium: 34–38 g, heavy: 39–43 g) and three antioxidant treatments (Vitamin E, Selenium, and VE+Se combination). The birds were reared for 35 days under uniform management conditions. Results showed a highly significant interaction (P<0.05) between DOC weight and antioxidant type on feed intake and weight gain during the starter phase, with the highest performance observed in heavy DOC chicks receiving the VE+Se combination. Physiological responses, including panting frequency and heart rate, were significantly affected by antioxidant treatment (P<0.05), with Se supplementation alone resulting in the lowest heart rate. Hematological parameters (erythrocytes, hematocrit, and hemoglobin) were not significantly affected (P>0.05), although numerically higher values were observed in medium and heavy DOC groups. Leukocyte profiles were also not significantly influenced (P>0.05), but VE+Se supplementation tended to increase monocyte and lymphocyte counts while reducing heterophils. Histological analysis of the intestine showed a significant interaction (P<0.05) on apical villus width, with the VE+Se group exhibiting more favorable villus morphology, indicating improved nutrient absorption. Overall, the combination of heavier DOC and VE+Se supplementation was effective in optimizing broiler performance and physiological resilience. © 2025 by the authors. Licensee ResearchersLinks Ltd, England, UK.
Doctoral Program of Animal Science, Faculty of Animal Science, Brawijaya University, Jl. Veteran, Jawa Timur, Malang, 65145, Indonesia; Department of Animal Science, Faculty of Animal Husbandry, Brawijaya University, Jl. Veteran, Jawa Timur, Malang, 65145, Indonesia; Program of Animal Science, Faculty of Agriculture, Universitas Muhammadiyah Sinjai, Jl. Teuku Umar, no. 8, Sinjai Utara, Sulawesi Selatan, Indonesia
