The selenium status of dairy cows in Estonia

Abstract

Based on earlier soil, forage and animal studies, Estonia is considered a Se-deficient country where Se supplementation of dairy cows has been routine practice for more than 10 years. To evaluate the current Se status of Estonian dairy cows, bulk tank milk samples (n = 218) from farms (n = 110) producing over 60% of the milk purchased in the counties of Estonia, were analysed for the Se concentration. Milk Se content ranged from 5 – 34 μg/kg. The mean Se content of all the samples was 16 μg/kg, indicating dairy cows’ Se status was from high-marginal to adequate depending on the reference level used. The results of the study provide evidence that the Se status of dairy cattle in Estonia has improved. Although Se status was satisfactory on 99 farms (90.8%) there were 10 farms (9.2%) with a milk Se concentration of less than or equal to 10 μg/kg where attention should be given to Se supplementation of the animals.

Keywords

• bulk milk
• trace elements
• silage
• nutrient deficiency