Increasing selenium in bovine blood by feed supplements or selenium injections

Area of Science:

• Animal Nutrition
• Trace Mineral Research
• Dairy Science

Background:

• Selenium is a vital trace mineral for livestock health.
• Ensuring adequate selenium levels in pregnant dairy cows is crucial for both dam and calf health.
• Dietary strategies are explored to optimize selenium status in cattle.

Purpose of the Study:

• To evaluate the efficacy of different feed supplements and selenium injections in elevating blood selenium levels in pregnant Holstein cows.
• To compare the impact of various dietary selenium sources on selenium bioavailability.
• To assess the transfer of supplemented selenium into milk.

Main Methods:

• Pregnant Holstein cows were assigned to different treatment groups.
• Treatments included dietary supplementation with soft coal fly ash, western grown grains, high selenium sweet clover, or selenium injections (sodium selenite).
• Blood and milk selenium concentrations were monitored throughout the study.

Main Results:

• All tested treatments resulted in a gradual increase in blood selenium concentrations.
• Supplementation with 4% fly ash by weight in the diet led to the highest blood selenium levels.
• Selenium concentrations in milk showed only minor increases across all treatment groups.

Conclusions:

• Dietary fly ash is a highly effective source for increasing blood selenium levels in pregnant dairy cows.
• While blood selenium is significantly impacted, milk selenium levels are minimally affected by these supplementation strategies.
• Fly ash presents a promising option for improving selenium status in pregnant cattle.