Abstract
Immunosuppression is a serious consequence of oxidative stress exposure that negatively affects the productivity and profitability of birds, as well as their well-being. Thus, the present investigation was designed to evaluate the potential of corn silk extract (CSE) supplementation to overcome the negative impacts of oxidative stress induced by corticosterone administration (CORT) in broiler chickens. A total of 280 one day old Cobb 500 male chicks were divided into four groups in 2 × 2 factorial arrangements. The experimental groups included CSE supplementation (0 or 500 mg/kg diet, from 20 to 35 days of age) and CORT administration (0 or 25 mg/kg diet, from 22 to 35 days of age) as independent factors. At the end of week five of age, production performance parameters were measured. The humoral and cell-mediated immune response parameters, redox status, and stress markers were determined. Data revealed deleterious effects of CORT administration on the broilers' body weight, body weight gain, and feed conversion ratio. Moreover, an exponential increase in stress marker levels, in addition to immunosuppression and redox imbalance, were associated with CORT administration. However, CSE supplementation, with its high total phenols content, partially alleviated the negative impacts of CORT administration, as shown by a significant improvement in immune response parameters and antioxidant activity, as well as a reduction in stress marker levels. Furthermore, CSE supplementation to non-stressed birds even significantly improved total antioxidant activity, total white blood cells (TWBCs) count, T-lymphocyte stimulating index, and wattle thickness. It can be concluded that, under stress conditions in commercial broiler farms, dietary CSE supplementation can strongly be recommended to modulate the negative impacts of stress. Therefore, CSE can be used as an effective immunomodulator and antioxidant agent to increase commercial broiler farm productivity and profitability.