Dietary vitamin E and selenium affect mastitis and milk quality

Area of Science:

• Animal Science
• Nutritional Biochemistry
• Veterinary Immunology

Background:

• Vitamin E and selenium are crucial antioxidants for cellular defense.
• Selenium deficiency is prevalent in dairy regions, impacting forage selenium content.
• Vitamin E deficiencies are common in periparturitum dairy cows, coinciding with high intramammary infection risk.

Purpose of the Study:

• To investigate the impact of vitamin E and selenium on immune function in dairy cows.
• To assess the effect of supplementation on polymorphonuclear neutrophil activity and mastitis incidence.
• To evaluate the efficacy of prepartum vitamin E supplementation on periparturient immune status.

Main Methods:

• Assessed the association between vitamin E and selenium deficiencies and intramammary infections (IMI).
• Evaluated the effect of dietary Se and vitamin E supplementation on PMN function post-challenge.
• Administered subcutaneous vitamin E injections prepartum and measured PMN alpha-tocopherol and bacterial kill capacity.

Main Results:

• Vitamin E and selenium deficiencies correlate with increased IMI incidence, severity, clinical mastitis, and somatic cell counts (SCC).
• Supplementation with Se and vitamin E enhanced PMN influx and intracellular bacterial killing post-challenge.
• Prepartum vitamin E injections increased PMN alpha-tocopherol and restored bacterial killing capacity in periparturient cows.

Conclusions:

• Vitamin E and selenium are vital for bovine mammary gland immune function, particularly PMN activity.
• Supplementation strategies can mitigate the negative impacts of deficiencies on mastitis resistance.
• Optimizing vitamin E and selenium status is crucial for dairy cow health and milk quality, especially around calving.