Factors affecting serum selenium and vitamin E concentrations in dairy cows

Area of Science:

• Veterinary Medicine
• Animal Nutrition
• Dairy Science

Background:

• Selenium and vitamin E supplementation is common in dairy cattle for disease prevention, especially for periparturient reproductive issues and mastitis.
• Establishing reference values for these micronutrients in postparturient dairy cattle is essential for herd health management.

Purpose of the Study:

• To determine reference values for serum vitamin E and selenium concentrations in postparturient dairy cattle.
• To investigate the influence of season and lactation stage on these serum micronutrient levels.

Main Methods:

• A 1-year study involving a stratified random sample of 50 dairy herds.
• Blood samples were collected twice from 10 recently parturient cows or 10% of the herd.
• Serum concentrations of vitamin E and selenium were analyzed.

Main Results:

• Mean serum vitamin E was 2.55 µg/ml and mean selenium was 78.12 ng/ml.
• Vitamin E levels were significantly higher in summer/fall compared to winter/spring (P < 0.05).
• Selenium levels were significantly lower in summer/fall compared to winter/spring (P < 0.05).
• Herd, season, and time since parturition significantly affected vitamin E and selenium concentrations (P < 0.02).

Conclusions:

• Serum vitamin E and selenium concentrations in postparturient dairy cattle exhibit seasonal variations.
• Lactation stage and herd-specific factors also influence these critical micronutrient levels.
• Findings provide valuable reference ranges and highlight the importance of monitoring vitamin E and selenium in dairy herds.