REDUCTION OF DEXAMETHASONE-INDUCED OXIDATIVE STRESS AND LIPID PEROXIDATION IN LAYING HENS BY DIETARY VITAMIN E SUPPLEMENTATION

Abstract

The objective of the present study is to research the effect of dietary vitamin E (Vit E) on laying performance, lipid peroxidation and antioxidative status in laying hens under experimentally induced oxidative stress conditions via Dexamethasone (DEX) administration. A total of 60 Egyptian local strain (Gimmizah) laying hens at 36 weeks of age were housed in individual cages in an open-sided building under a 16 hr light: 8 hr dark lighting schedule. The birds were randomly divided into four experimentally treatments: DEX (4 mg/hen/day); Vit. E (200 mg/kg diet); DEX+Vit. E (4 mg/hen/day+ 200 mg/kg diet respectively); and control (n= 15). The birds were provided with commercial feed and water ad libitum. All treatments lasted for 7 successive days. Oxidative stress induced by DEX injections significantly reduced egg production and egg weight. Vit. E alleviated this reduction when supplemented to the stress-induced hens, compared to DEX treatment. A high level of yolk lipid oxidation was associated with oxidative stress treatment and it was reduced by Vit E supplementation. It could be concluded that supernutritional levels of Vit E (200 mg/kg diet) may contribute in enhancing laying performance and antioxidative status of laying hens under stress conditions.