{
  "url": "https://openlegislation.uk/eu-regulation-2009-152/annex-III/division-G/division-8",
  "json_url": "https://openlegislation.uk/eu-regulation-2009-152/annex-III/division-G/division-8.json",
  "legislation": "eur/2009/152",
  "legislation_title": "Commission Regulation (EC) No 152/2009 of 27 January 2009 laying down the methods of sampling and analysis for the official control of feed (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2009-152",
  "path": "annex/III/division/G/division/8",
  "kind": "division",
  "number": "8",
  "heading": "Results of a collaborative study",
  "text": "An EC collaborative study (4th intercomparison) was arranged in which three samples were analysed by up to 12 laboratories to certify the method for hydrolysis. Replicate (5) analyses were performed on each sample. The results are given in the following table:\nSample 1Pig feed\nSample 2Pig feed supplemented with L-tryptophan\nSample 3Feed concentrate for pigs\nL\n12\n12\n12\nn\n50\n55\n50\nMean [g/kg]\n2,42\n3,4\n4,22\nsr [g/kg]\n0,05\n0,05\n0,08\nr [g/kg]\n0,14\n0,14\n0,22\nCVr [%]\n1,9\n1,6\n1,9\nSR [g/kg]\n0,15\n0,2\n0,09\nR [g/kg]\n0,42\n0,56\n0,25\nCVR [%]\n6,3\n6,0\n2,2\nLnumber of laboratories submitting results\nnnumber of single results retained eliminating outliers (identified by Cochran, Dixon outlier test)\nsr standard deviation of repeatability\nSR standard deviation of reproducibility\nrrepeatability\nRreproducibility\nCVr coefficient of variation of repeatability, %\nCVR coefficient of variation of reproducibility, %\nAnother EC collaborative study (3rd intercomparison) was arranged in which two samples were analysed by up to 13 laboratories to certify the method for extraction of free tryptophan. Replicate (5) analyses were performed on each sample. The results are given in the following table:\nSample 4Wheat and soya mixture\nSample 5Wheat and soya mixture (= sample 4) with added tryptophan (0,457g/kg1)\nL\n12\n12\nn\n55\n60\nMean [g/kg]\n0,391\n0,931\nsr [g/kg]\n0,005\n0,012\nr [g/kg]\n0,014\n0,034\nCVr [%]\n1,34\n1,34\nSR [g/kg]\n0,018\n0,048\nR [g/kg]\n0,05\n0,134\nCVR [%]\n4,71\n5,11\nLnumber of laboratories submitting results\nnnumber of single results retained after eliminating outliers (identified by Cochran, Dixon outlier test)\nsr standard deviation of repeatability\nSR standard deviation of reproducibility\nrrepeatability\nRreproducibility\nCVr coefficient of variation of repeatability, %\nCVR coefficient of variation of reproducibility, %\nAnother EC intercomparison study was arranged in which four samples were analysed by up to 7 laboratories with the aim of a tryptophan certification for hydrolysis. The results are given below. Replicate (5) analyses were performed on each sample.\nSample 1Mixed pig feed(CRM 117)\nSample 2Low fat fish meal(CRM 118)\nSample 3Soybean meal(CRM 119)\nSample 4Skimmed milk powder(CRM 120)\nL\n7\n7\n7\n7\nn\n25\n30\n30\n30\nMean [g/kg]\n2,064\n8,801\n6,882\n5,236\nsr [g/kg]\n0,021\n0,101\n0,089\n0,04\nr [g/kg]\n0,059\n0,283\n0,249\n0,112\nCVr [%]\n1,04\n1,15\n1,3\n0,76\nSR [g/kg]\n0,031\n0,413\n0,283\n0,221\nR [g/kg]\n0,087\n1,156\n0,792\n0,619\nCVR [%]\n1,48\n4,69\n4,11\n4,22\nLnumber of laboratories submitting results\nnnumber of single results retained after eliminating outliers (identified by Cochran, Dixon outlier test)\nsr standard deviation of repeatability\nSR standard deviation of reproducibility\nrrepeatability\nRreproducibility\nCVr coefficient of variation of repeatability, %\nCVR coefficient of variation of reproducibility, %",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2009/152/annex/III/division/G/division/8",
    "retrieved_at": "2026-11-01T14:51:38.610873+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}