The influence of vitamin E on immune function and response to vaccination in older horses.

The research article investigates the impact of vitamin E on the immune performance and vaccine response of aged horses. It illustrates how vitamin E improves certain elements of cellular and humoral immune function, like immune cells’ bacterial fighting ability and certain types of immunoglobulin production.

Study Participants and Method

• In the study, mostly older horses, weighing around 523 kg and aged between 7 to 26 years were given a daily oral supplement of either all-rac-alpha-tocopheryl acetate, a form of Vitamin E, or a placebo for 16 weeks.
• The number of horses in both groups was the same; however, a horse from each group was removed due to issues unrelated to the study.

Measurements and Examinations

• The research investigated various parameters related to immune function, including the serum alpha-tocopherol concentration, the bacterial killing ability of neutrophils and monocytes, lysozyme activity, and levels of different classes of immunoglobulins (IgG(a), IgG(b), IgG(T), and IgM).
• It also examined the neutralizing antibody production in response to West Nile virus vaccination.

Key Findings

• Vitamin E-supplemented horses showed a higher serum alpha-tocopherol concentration compared to those supplemented with placebos.
• Increased bacterial killing ability of monocytes and neutrophils was observed in the vitamin E-supplemented group.
• Vitamin E-supplemented horses also showed higher concentrations of IgG(a) and IgG(T) immunoglobulins, but their production of IgG(b) was lesser than placebo-supplemented horses.
• No change was observed in the production of IgM immunoglobulins.
• The neutralizing antibody response to vaccination against West Nile virus wasn’t impacted by vitamin E supplementation.
• However, there was an increase in serum lysozyme concentration in placebo-supplemented horses, while this increase was delayed until the 12th week in vitamin-E supplemented horses.

Conclusion

• The research concluded that vitamin E supplementation in older horses influences certain areas of cell-mediated and humoral immune function, with differential effects.
• Even though the study presents significant insights, it recommends further research to fully understand the influence of vitamin E on horse immunity.