A survey of whole blood selenium concentrations of horses in Maryland.

This study investigated the selenium levels in the whole blood samples of horses in four northern Maryland counties, discovering the influences of farming practices, pasture maintenance and diet on the selenium status of horses.

Research Objective and Methodology

• The study aimed to assess the whole blood selenium concentrations in a random horse population sample in northern Maryland. Selenium is an essential mineral for horses, and insufficiency or excess can harm a horse’s health.
• The researchers chose samples from 202 horses from 74 farms in four adjoining counties. The spread of these samples offered a good representation of the equine population in that geographic area.
• The levels of selenium were determined based on the whole blood concentration. The research deemed a level of 0.100 parts per million (ppm) as satisfactory, while amounts below this benchmark were categorized as deficient or marginal.

Findings

• The mean blood selenium concentration among the horses was 0.137 ppm, with the range varying from 0.050 ppm to 0.266 ppm, displaying a standard deviation of 0.041 ppm.
• From the 202 horses, 38 (18.8%) had a selenium level equal to or less than the 0.099 ppm benchmark, indicating potential deficiency.
• Of the 74 farms, 21 (28.4%) held at least one horse with a selenium level that was considered deficient or marginal.
• The research found farming practices influenced selenium status in horses. Those kept on pasture, those not used regularly, or those without a diet supplemented with minerals and vitamins were more likely to have abnormal selenium levels.

Implications

• The research highlights the importance of selenium in maintaining horse health. The high number of horses with low selenium levels indicates the potential risk of deficiency-related health problems.
• The results suggest that farm management practices concerning horse usage, pasture management, and dietary supplementation can significantly influence a horse’s selenium status. This insight is valuable for both farmers and veterinarians, who often manage diet and nutrition for horse health.
• This study provides a basis for further research on dietary needs and supplementation in other livestock or in different geographical areas.