Nutritional supplementation with vitamin E or plant extracts affects redox and immune response in early lactating dairy cows

In dairy cows, early lactation is a period prone to oxidative stress, inflammation and health problems. Our objective was to investigate the effects of the nutritional supplementation of early lactating cows with plant extracts or vitamin E on physiological and immunological status. Forty-five Holstein cows were divided into three groups: control group (n = 15), vitamin E group (n = 16) (3,000 IU/d for 3 weeks before and 1,000 IU/d after calving), and plant extract group (n = 14) (10 g/d only after calving). Their redox and immune status were monitored during the first 12 weeks of lactation, every four week. In week 12, plasma malondialdehyde levels in plasma were lower in the vitamin E and plant extract groups than in the control group. The vitamin E and plant extract groups had lower ex vivo plasma CCL4, IL6 and IL8 cytokine levels, lower proportions of blood regulatory neutrophils, and less ROS production by blood neutrophils than the control group. In terms of immune response, vitamin E and plant extracts down-regulated the gene expression of FABP3 in the milk mammary epithelial cells of multiparous cows. Therefore, supplementation with either vitamin E or plant extracts could prevent systemic hyper-inflammation and improve the immune response during early lactation.