Abstract

Selenium (Se) as a micronutrient in ruminant diet plays a vital role in antioxidant systems and preventing cellular damage. High concentrate diets cause abnormal fermentation in rumen that leads to increased oxidative stress (OS), leading to rumen epithelial tissue damage and apoptosis in goats. This study evaluated the influence of dietary Se on OS, rumen epithelium and apoptosis in goats. Thirty cross-bred goats (12-16 weeks, 10-13 kg) were allocated to group LC (low concentrate diet), HC (high concentrate diet) and HC-SY (HC + selenium yeast at 0.5 mg/kg diet) for 75 days. Rumen epithelial tissue samples were analyzed for the biomarkers of OS and mRNA expression of apoptotic pathway genes. Histomorphology of rumen epithelium showed reduced OS and improved epithelial morphology in group HC-SY than in HC. Malondialdehyde (MDA) raised (P < 0.0001) in HC than LC but reduced (P < 0.001) in HC-SY than HC. Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activity escalated (P < 0.05) in HC-SY compared to HC. mRNA gene expression of apoptotic pathway genes Bax, Caspase-3, and -9 were upregulated (P < 0.05) and the Bcl2 and Bcl2/Bax ratio downregulated (P < 0.05) in group HC than in LC, however mRNA expression level of Bax, Caspase-3 and -9 were downregulated (P < 0.0001) while Bcl2, and Bcl2/Bax ratio were upregulated (P < 0.01) in HC-SY. In conclusion, it is suggested that Se addition to high concentrate diet improves ruminal epithelium via alleviating diet-induced OS and apoptosis in rumen of goats.