Dietary Antioxidants at Supranutritional Doses Modulate Skeletal Muscle Heat Shock Protein and Inflammatory Gene Expression in Sheep Exposed to Heat Stress

Abstract

The objective of this study was to investigate the effects of chronic heat (thermal) stress and dietary antioxidant supplementation on the expression of heat shock proteins and inflammatory genes in the skeletal muscle of sheep. Twenty-four Merino × Poll Dorset crossbred ewes were allocated to either a control (10 IU vitamin E and 0.24 mg Se/kg DM) or high-antioxidant (VitE+Se; 100 IU vitamin E and 1.20 mg Se/kg DM) diet and were exposed to 2 thermal (temperature) treatments (thermoneutral [TN]: 18°C–21°C and 26%–30% relative humidity; heat stress [HS]: 28°C–40°C and 40%–50% relative humidity) for 1 wk. Physiological parameters were recorded daily, and muscle biopsies were conducted at the e..