Supplementing young cattle with a rumen-protected grape extract around vaccination increases humoral response and antioxidant defenses

Vaccination is an important mainstay of biosecurity and disease prevention in livestock farming. Vaccination failures represent an economic burden for the farmer. Polyphenol supplementation, known for its antioxidant properties, could help reduce oxidative damage and improve the success of vaccination. We evaluated the effect of a rumen-protected grape extract (RPGE) supplementation around vaccination on the immune response in young ruminants. 22 young female cattle (aged 6 to 8 months), born in the same dairy farm, were randomly divided into 2 groups. One group (BP-O, n = 11) was supplemented with a RPGE (Nor-Grape® BP-O, Nor-Feed, France), whilst a control group (CTL, n = 11) was not. All animals were vaccinated (D14) with an inactivated vaccine against PI-3 V and BRSV. A booster was given 3 weeks later (D35). Supplementation began 15 days before vaccination (D0) and ended 15 days after the last injection (D49). Antibody titers and total antioxidant status (TAS) were performed on blood samples drawn on D0, D35 and D56. Results show that the BP-O group tended to have a greater overall antibody response to BRSV and PI-3 V on D56 (P < 0.10) and PI-3 V titer was significantly higher in the BP-O group on D35 (p < 0.05). A greater total antioxidant capacity (P<0.05 at D56) was also observed in the supplemented group. Results also showed a strong correlation between PI-3 V antibody titers and TAS (p < 0.001). Thus, since supplemented animals became seropositive faster and long-term immunity appeared to be improved, this supplementation strategy could be of interest to enhance the immune response during a vaccination episode by reducing oxidative stress.