SELENIUM STATUS OF FEEDSTUFFS AND GRAZING EWES IN SERBIA

A total of 221 feedstuff samples (187 grain samples and 34 hay samples) were collected from 13 different locations on the territory of the Republic of Serbia. The results expressed as mu g/kg have shown an average selenium content in grain samples of 34.3 +/- 17.1 and 53.8 +/- 18.7 in hay samples. However, a distinct difference was noted between samples collected fron the locations north of the river Danube (52.8 +/- 20.0 and 73.4 +/- 21.3 for grain and hay samples, respectively) compred to the locations south of the Danube (23.3 +/- 15.4 and 41.7 +/- 17.1 for grain and hay samples, respectively). GPx activity was measured in a total of 58 blood plasma samples collected from ewes grazing on 5 different locations. The average GPx activity was 157.4 +/- 61.9 mu kat/L and it followed a pattern similar to the distribution of Se in feedstuffs. GPx activity was higher in samples collected north of the Danube (212.8 +/- 91.2 mu kat/L), compared to ewes south of the Danube (66.9 +/- 14.0 mu kat/L). According to the obtained results and literature data Serbia can be described as a selenium deficient area, showing a marked deficiency on the locations south of the Danube.