Vitamin E and Selenium Decreased Cortisol in Cattle

Twenty dairy cows with left abomasal displacement were used to investigate the effects of vitamin E and selenium treatment on blood cortisol in dairy cows stressed by omentopexy. The cows were randomly divided into two groups. Ten hours before surgery 6 g of DL-α-tocopheryl acetate (6 mg.kg⁻¹) and 67 mg of natrium selenite (0.1 mg.kg⁻¹) in a volume of 40 ml were administered subcutaneously to 10 cows; the control animals (n = 10) received an equivalent volume of injectable water (40 ml). The injection of vitamin E and selenium produced a rapid rise (P < 0.05) in blood α-tocopherol and selenium concentrations. The serum vitamin E increased several times ten hours after vitamin E and Se injection and raised continuously to the highest average concentration of 21.6 mg.l⁻¹ at hour 24 after the surgery. The highest selenium concentration was seen ten hours after selenium administration with holding the increased concentrations in comparison to initial ones during the whole study. Serum cortisol increased in both groups after surgery. The highest cortisol concentrations were reached at one hour after surgery in the experimental and control group (56.7 ± 28.8 and 65.3 ± 26.1 μg.l⁻¹, respectively). A return to the levels similar to the initial ones was recognized 24 hours after the surgery. The ANOVA revealed a significant effect of vitamin E and selenium injection on serum cortisol (P < 0.05). In conclusion, we have demonstrated that abdominal surgery resulted in typical stress changes with a weaker cortisol response to the abdominal surgery in animals treated with vitamin E and selenium.