Dietary hot red pepper powder modulates laying performance, hematology profile, and hepatic antioxidant status in laying hens under tropical conditions

Hot red pepper (HRP) has emerged as a phytogenic feed additive with the potential to enhance laying performance in laying hens by improving gut health and mitigating oxidative stress. This study aimed to evaluate the effects of dietary inclusion of HRP powder on the productive performance, hematological and biochemical profiles, intestinal morphology, oxidative stress markers, and liver histopathology of laying hens reared under tropical conditions. A total of 100 Novogen laying hens were randomly assigned to four dietary treatments for eight weeks: a basal control diet and diets supplemented with 0.25%, 0.5%, or 0.75% HRP powder. Dietary supplementation with 0.25% and 0.5% HRP improved hen-day egg production during the first period (P < 0.05). HRP inclusion significantly reduced serum cholesterol levels (P < 0.05). Additionally, HRP supplementation (0.25–0.75%) increased lymphocyte counts (P < 0.001) while decreasing total leukocytes, heterophils, and the heterophil-to-lymphocyte (H/L) ratio (P < 0.001). Regarding gut environment, dietary inclusion of 0.5%-0.75% HRP decreased caecal pH, whereas 0.75% HRP reduced colon pH (P < 0.05). For antioxidant status, HRP at 0.25–0.5% enhanced hepatic superoxide dismutase activity (P < 0.05), while all inclusion levels (0.5–0.75%) lowered malondialdehyde concentrations (P < 0.05). Histopathological evaluation confirmed reduced liver inflammation and cellular degeneration. Overall, dietary HRP improves productive performance, physiological status, gut function, and liver health in laying hens under tropical conditions, with 0.5% providing the most consistent benefits, supporting its application as an effective phytogenic feed additive in poultry production.