title: [Trend of the selenium supply of cattle in Germany, Austria, Switzerland, and Denmark. Retrospective analysis of serum samples of the years 2006-2015].
abstract: OBJECTIVE
  An optimal selenium supply of cattle is essential, because an insufficiency can lead to health disorders and reduced performance. The aim of the study was to retrospectively evaluate the selenium supply of cattle in Germany, Austria, Switzerland, and Denmark.
  
  
  METHODS
  Serum samples from 45  068 cattle with unknown clinical status originating from countries all across Europe, which had been sent by veterinarians to the IDEXX Laboratory Ludwigsburg, Germany, between January 1st, 2006 and June 30th, 2015, were routinely analyzed for the selenium concentration by means of Inductively Coupled Plasma Mass Spectrometry. A total of 40  949 samples (30  462 from Germany, 4004 from Austria, 3232 from Switzerland, 3251 from Denmark) were included in the evaluation. Results were categorized as follows: 50-150 µg/l: sufficient supply, < 50 µg/l: supply too low, > 150 µg/l: supply too high.
  
  
  RESULTS
  During the observation period, a generalized trend towards a decreasing selenium supply was clear. Denmark showed the best selenium supply (77.4% of samples indicating a sufficient supply); however, even in this country a tendency towards a deterioration was seen. A very poor situation with a strongly decreasing selenium supply was observed in Austria, followed by Germany (38% and 30% of samples, respectively, indicating an undersupply). For Switzerland, a constantly poor selenium supply was found (49% of samples indicating an undersupply).
  
  
  CONCLUSIONS
  Due to the ongoing trend of a selenium undersupply in cattle herds, it is recommended to control the serum selenium concentration annually and supplement this trace element via mineral food when necessary.
authors.affiliation: Dr. Anja Müller, Vet Med Labor GmbH, IDEXX Laboratories, Mörikestraße 28/3, 71636 Ludwigsburg, E-Mail: anja-mueller@idexx.com.
authors.forename: A
authors.initials: A
authors.lastname: Müller
authors.forename: B
authors.initials: B
authors.lastname: Freude
mesh_terms: D000821:Animal Feed / Q000592:standards; D000818:Animals; D001317:Austria; D002417:Cattle / Q000097:blood* / Q000378:metabolism; D003718:Denmark; D019587:Dietary Supplements; D005858:Germany; D012189:Retrospective Studies; D012643:Selenium / Q000008:administration & dosage / Q000097:blood*; D013557:Switzerland
chemical_list: D012643:Selenium
keywords: Trace element supply; laboratory diagnostics; mineral feed; supplementation