An experiment was carried out to investigate the effect of vitamin E on the metabolic impact of heat stress in hens. The study included 150 Leghorn laying hens, which were assigned to 2 groups and initially subjected to the same environmental conditions. Diets were based on standard layer rations with 30, 80, or 105 mg of vitamin E/kg. All birds were kept in 45% relative humidity (RH) and at a room temperature of 21 °C for first 3 weeks for adaptation. In the fourth week the temperature and RH were increased to 35 °C and 65%, respectively, in the experimental group. Before, during, and after exposure to heat stress blood samples were taken from both groups. Vitamin E analyses were determined by HPLC. Biochemical parameters were analyzed spectrophotometrically. Statistically significant (P ≤ 0.05) increases in plasma malondialdehyde (MDA), erythrocyte MDA, glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD), and egg yolk MDA concentration, and a decrease in plasma vitamin E were seen in the experimental group during heat stress. Egg quality parameters also decreased in the experimental group during heat stress. Dietary supplementation with higher levels of vitamin E alleviated some of the metabolic consequences of heat stress; there was no evidence of a beneficial effect on egg production during heat stress within the dietary range investigated.
Vitamin E, laying hens, antioxidant defense system, heat stress
YARDİBİ, HASRET and HOŞTÜRK, GÜLHAN TÜRKAY (2008) "The Effects of Vitamin E on the Antioxidant System, Egg Production, and Egg Quality in Heat Stressed Laying Hens," Turkish Journal of Veterinary & Animal Sciences: Vol. 32: No. 5, Article 1. Available at: https://journals.tubitak.gov.tr/veterinary/vol32/iss5/1